Rear body structure
The rear body structure with rubber bushings and a truss-structured brace reduces road noise transmission by absorbing vibrations, enhancing rigidity and weight reduction, thereby improving vehicle comfort and performance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2022-07-12
- Publication Date
- 2026-06-23
AI Technical Summary
Vibration from tires, commonly known as road noise, is transmitted to the passenger compartment through the suspension member and rear side member, leading to discomfort for vehicle occupants.
A rear body structure comprising a pair of rear side members, a suspension member with side beams and cross beams, and a brace connected via rubber bushings to absorb and reduce road noise transmission.
The rubber bushings effectively attenuate road noise, while the truss structure of the brace enhances rigidity and reduces weight, improving passenger compartment comfort and vehicle performance.
Smart Images
Figure 0007878955000001 
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Abstract
Description
Technical Field
[0001] The technology disclosed in this specification relates to the rear body structure.
Background Art
[0002] Patent Document 1 discloses a technology related to a suspension member at the rear of a vehicle body. The suspension member includes a pair of side beams and a cross beam. Each of the pair of side beams is connected to each of a pair of rear side members. The cross beam is connected to each of the pair of side beams. The suspension member supports the base of the lower arm. A hub is attached to the tip of the lower arm. The hub rotatably supports the axle.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] During driving, the vibration of the tire is transmitted to the passenger compartment. This vibration is commonly called "road noise". Road noise is transmitted to the passenger compartment through the suspension member and the rear side member. This specification provides a technology for reducing road noise transmitted to the passenger compartment.
Means for Solving the Problems
[0005] The rear body structure disclosed herein comprises a pair of rear side members extending in the longitudinal direction of the vehicle body, a suspension member connected to the rear side members, and a brace connected to the pair of rear side members and the suspension member. The suspension member comprises a pair of side beams extending in the longitudinal direction of the vehicle body, and a cross beam connected to each of the pair of side beams. Each of the pair of side beams is connected to each of the pair of rear side members via a first rubber bushing. The brace is connected to the cross beam via a second rubber bushing and is also connected to each of the pair of rear side members. Road noise is absorbed by the first and second rubber bushings, so that road noise transmitted to the passenger compartment is reduced.
[0006] The brace should be connected to the crossbeam at two points, with a truss structure between the two points. This allows for weight reduction of the brace.
[0007] The front end of each side beam is connected to the corresponding rear side member via a first rubber bushing, and the brace is preferably connected to the rear side member by a bolt that passes through the first rubber bushing. The connection point between the rear side member and the side beam, and the connection point between the rear side member and the brace can be combined into one.
[0008] Details of the technology disclosed herein and further improvements are described in the following "Modes for Carrying Out the Invention". [Brief explanation of the drawing]
[0009] [Figure 1] This is a plan view of the rear of the vehicle body adopting the rear structure of the embodiment. [Figure 2] This is a front view of the suspension member connected to the rear side member. [Figure 3] This is a cross-sectional view along line III-III in Figure 2. [Figure 4] This is a cross-sectional view along line IV-IV in Figure 2. [Modes for carrying out the invention]
[0010] The rear body structure of the embodiment will be described with reference to the drawings. The rear body structure of the embodiment is applied to the rear of the vehicle body 2. Figure 1 shows a plan view of the rear of the vehicle body 2. Figure 1 is a top view of the suspension member 10 connected to a pair of rear side members 3a and 3b. The suspension member 10 is part of the structure that supports the rear tire 91. Figure 2 is a front view of the suspension member 10 connected to the rear side members 3a and 3b.
[0011] The suspension member 10 includes a pair of side beams 11a and 11b and two cross beams (a front cross beam 12 and a rear cross beam 13). The pair of side beams 11a and 11b extend in the longitudinal direction of the vehicle body. Each of the pair of side beams 11a and 11b is connected to the corresponding rear side members 3a and 3b via a first mount 30. The front and rear ends of the side beam 11a are each connected to the rear side member 3a via the first mount 30. The front and rear ends of the side beam 11b are each connected to the rear side member 3b via the first mount 30. The connection between the side beams 11a (11b) and the rear side members 3a (3b) will be described in detail later.
[0012] The front crossbeam 12 is connected to each of the pair of side beams 11a and 11b. The front crossbeam 12 is welded to the front of the side beams 11a and 11b. The rear crossbeam 13 is also connected to each of the pair of side beams 11a and 11b. The rear crossbeam 13 is welded to the rear of the side beams 11a and 11b.
[0013] The pair of side beams 11a and 11b are beams that extend in the longitudinal direction of the vehicle body, while the two cross beams (front cross beam 12 and rear cross beam 13) are beams that extend in the width direction of the vehicle.
[0014] The base of the lower arm 93 is connected to the side beam 11a (11b), and the hub 92 is connected to the tip of the lower arm 93. The hub 92 rotatably supports the rear shaft 94, and the rear tires 91 are connected to both ends of the rear shaft 94. In Figure 1, the lower arm 93, hub 92, and rear shaft 94 are drawn with dashed lines (two-dot lines). The hub 92 is also supported by the upper arm, but the upper arm is not shown. The suspension spring and suspension damper are also not shown.
[0015] In the vehicle body rear structure of this embodiment, a brace 20 is employed that connects a pair of rear side members 3a and 3b to the front cross beam 12. The brace 20 is a beam extending in the vehicle width direction and is made of metal. Each end of the brace 20 is connected to the respective rear side members 3a and 3b. The brace 20 is connected to the front cross beam 12 at two points (two second mounts 40) between its ends. The brace 20 passes over the front cross beam 12, and its ends are located below the rear side members 3a and 3b.
[0016] The ends of the brace 20 are located below the rear side members 3a (3b) and also below the side beams 11a (11b). As shown in Figure 1, the connection point between the end of the brace 20 and the rear side members 3a (3b) coincides with the connection point between the rear side members 3a (3b) and the side beams 11a (11b) when viewed from above. The connection structure between the rear side members 3a (3b), the brace 20, and the side beams 11a (11b) will be explained in detail later.
[0017] The brace 20 has a truss structure between the two points (two second mounts) where it is connected to the front crossbeam 12. More specifically, between the two second mounts 40, the brace 20 consists of two parallel main beams 21a and 21b and multiple connecting beams 22 that connect the two main beams 21a and 21b. In Figure 1, only the two connecting beams are labeled with reference numeral 22, and the reference numerals are omitted for the remaining connecting beams.
[0018] The two connecting beams 22 are connected to the main beam 21a (or 21b) at one location. In the truss structure, the space surrounded by the main beam 21a or the main beam 21b and a pair of adjacent connecting beams 22 forms a triangle. As shown in FIG. 1, when viewed from above, between the two second mounts 40, the brace 20 is such that all the spaces surrounded by the beams (the main beams 21a, 21b, and the plurality of connecting beams 22) form triangles. The truss structure can achieve light weight and high rigidity.
[0019] FIG. 3 shows a cross-section taken along line III-III of FIG. 2. FIG. 3 shows the internal structure of the first mount 30 and the connection structure of the rear side member 3a, the side beam 11a, and the brace 20.
[0020] The first mount 30 includes a first rubber bush 31, discs 32, 36, a bolt 33, a nut 34, and a cylinder 35. The first rubber bush 31 is sandwiched between the lower surface of the rear side member 3a and the disc 32, and is fixed to the rear side member 3a with the bolt 33 and the nut 34. The side beam 11a is provided with a through hole 19, and the through hole 19 penetrates the side beam 11a in the vertical direction. The first rubber bush 31 has rubber flanges at its upper and lower edges. The first rubber bush 31 is press-fitted into the through hole 19 of the side beam 11a, and the side beam 11a is located between the upper and lower rubber flanges. As shown in FIG. 3, the side beam 11a is not in direct contact with the rear side member 3a, and is connected to the rear side member 3a via the first rubber bush 31.
[0021] The first rubber bush 31 is provided with a through hole 39, and the through hole 39 penetrates the first rubber bush 31 in the vertical direction. The cylinder 35 is disposed in the through hole 39, and the bolt 33 passes through the cylinder 35. The cylinder 35 is made of metal, and the tightening force by the bolt 33 is received by the cylinder 35. The first rubber bush 31 does not receive a large force from the bolt 33.
[0022] The bolt 33 also passes through the two discs 32 and 36, and the brace 20 is sandwiched between the two discs 32 and 36. In other words, the brace 20 is clamped together with the rear side member 3a. The brace 20 is rigidly fixed to the rear side member 3a. In other words, there is no damping element between the brace 20 and the rear side member 3a.
[0023] The front end of the side beam 11a is connected to the rear side member 3a via the first rubber bush 31. The end of the brace 20 is rigidly connected to the rear side member 3a by a bolt 33 that passes through the first rubber bush 31. The first mount 30 is also used at the connection point between the rear end of the side beam 11a and the rear side member 3a. However, the brace 20 is not connected to the first mount 30 at the rear end of the side beam 11a.
[0024] The structure of the connection point between the side beam 11b and the rear side member 3b is the same as the structure of the connection point between the side beam 11a and the rear side member 3a.
[0025] Fig. 4 shows a cross-section taken along the line IV-IV of Fig. 2. Fig. 4 shows the internal structure of the second mount 40 and the connection structure between the front cross beam 12 and the brace 20.
[0026] The second mount 40 includes a second rubber bush 41, a disc 42, and a bolt 43. The second rubber bush 41 is sandwiched between the upper surface of the front cross beam 12 and the disc 42, and is fixed to the front cross beam 12 by the bolt 43. The brace 20 is provided with a through hole 29, and the through hole 29 penetrates the brace 20 in the vertical direction. The second rubber bush 41 has rubber flanges at its upper and lower edges. The second rubber bush 41 is press-fitted into the through hole 29, and the brace 20 is located between the upper and lower rubber flanges. As shown in Fig. 4, the brace 20 is not in direct contact with the front cross beam 12, and is connected to the front cross beam 12 via the second rubber bush 41.
[0027] The advantages of using brace 20 are explained below. Road noise is transmitted to the passenger compartment through the side beams 11a and 11b and rear side members 3a and 3b of the suspension member 10. Some of the road noise is transmitted to the rear side members 3a and 3b through brace 20 and further to the passenger compartment. A first rubber bush 31 is sandwiched between the side beam 11a (11b) and the rear side member 3a (3b), and the first rubber bush 31 attenuates the road noise. A second rubber bush 41 is sandwiched between the front cross beam 12 of the suspension member 10 and brace 20, and the second rubber bush 41 also attenuates the road noise. By using brace 20 and the second rubber bush 41, the amount of road noise transmitted to the passenger compartment can be reduced.
[0028] The ends of the brace 20 are connected to the rear side members 3a and 3b, and at two points between the ends, it is connected to the front cross beam 12. This structure improves the rigidity of the suspension member 10 around the roll axis. The ends of the brace 20 are located below the side beams 11a (11b) of the suspension member 10 and pass over the front cross beam 12. The lower side of the brace 20 is connected to the upper side of the front cross beam 12 via the second rubber bush 41. This structure effectively dampens vibrations around the pitch axis of the suspension member 10. Note that the roll axis refers to the axis extending in the longitudinal direction of the vehicle body 2, and the pitch axis refers to the axis extending in the width direction of the vehicle body 2.
[0029] Other features of the rear body structure described in the embodiment are listed below. Viewed from above, the front end of the side beam 11a (11b) and the end of the brace 20 overlap, and they are connected to the rear side member 3a (3b) at one point. More specifically, the brace 20 is fixed to the rear side member 3a (3b) by a bolt 33 that passes through a first rubber bush 31 sandwiched between the side beam 11a (11b) and the rear side member 3a (3b). The brace 20 can be fixed to the rear side member 3a (3b) by a first mount 30 including the first rubber bush 31.
[0030] The second mount 40 may be used for other purposes. For example, the second mount may be used to attach an electric motor that drives the rear tires to the suspension member 10. When an electric motor is mounted, the brace 20 is not necessary because the weight of the electric motor attached to the suspension member 10 contributes to reducing road noise.
[0031] Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technologies described in the claims include various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving even one of these objectives itself constitutes technical usefulness. [Explanation of symbols]
[0032] 2: Body 3a, 3b: Rear side member 10: Suspension member 11a, 11b: Side beam 12: Front cross beam 13: Rear cross beam 19, 29, 39: Through hole 20: Brace 21a, 21b: Main beam 22: Connecting beam 30: First mount 31: First rubber bush 32, 36, 42: Disc 33, 43: Bolt 34: Nut 35: Cylinder 40: Second mount 41: Second rubber bush 91: Rear tire 92: Hub 93: Lower arm 94: Rear shaft
Claims
1. A pair of rear side members extending in the front-to-rear direction of the vehicle body, The suspension member connected to the aforementioned rear side member, A pair of rear side members and a brace connected to the suspension member, It is equipped with, The aforementioned suspension member is A pair of side beams extending in the longitudinal direction of the vehicle body, each of which is connected to the corresponding rear side member via a first rubber bushing, It is equipped with a cross beam connected to each of the pair of side beams, Each end of the brace is connected to the rear side member and the side beam via the first rubber bushing, and each end is located below the side beam. The brace is connected to the crossbeam at two points via a second rubber bushing and passes over the crossbeam. Rear body structure.
2. The rear body structure of the vehicle according to claim 1, wherein the brace has a truss structure between the two locations.