Suspension cross member

Abstract

To provide a suspension cross member which is advantageous for achieving protection of a power train during rear collision.SOLUTION: At a point near a rear end of a pair of side members 14 in a side view, a pair of mount brackets 22 for first power train, which are positioned in the rear of a rear end of a power train 12 and below a rear cross member 18, are provided. The pair of mount brackets 22 for first power train reliably receives a collision load inputted during rear collision, and the inputted impact load can be efficiently transmitted the whole of a suspension cross member 10 via the pair of side members 14.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a suspension cross member. [Background technology]

[0002] A structure has been proposed in which a power train including an engine is supported by a suspension cross member that swingably supports the front wheels via suspension arms (see Patent Document 1). It is conceivable that such a suspension cross member could be applied to the rear wheels of an electric vehicle powered by a motor, with the suspension cross member supporting the rear wheels in a swingable manner via suspension arms, and the suspension cross member supporting the powertrain of the electric vehicle. Generally, the powertrain of an electric vehicle includes electrical components such as a reduction gear and a converter in addition to the motor, which increases the size of the powertrain and increases the vertical dimension of the powertrain. Therefore, the powertrain may be positioned so that its lower portion protrudes downward below the lower surface of the suspension cross member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-172481 Summary of the Invention [Problem to be solved by the invention]

[0004] In the event of a rear-end collision on a vehicle equipped with a suspension cross member supporting such a powertrain, the upper part of the rear-end colliding object (barrier) collides with the rear of the suspension cross member, absorbing the collision load and preventing the upper part of the object from interfering with the rear of the powertrain. On the other hand, the lower part of an object colliding from behind may become wedged under the rear of the suspension cross member, and the wedged object may interfere with the lower part of the powertrain, which protrudes downward from the underside of the suspension cross member. The present invention has been made in view of the above circumstances, and has as its object to provide a suspension cross member that is advantageous in protecting the powertrain in the event of a rear-end collision. [Means for solving the problem]

[0005] In order to achieve the above-mentioned object, one embodiment of the present invention comprises a pair of side members extending in the fore-and-aft direction of the vehicle at a distance in the vehicle width direction, and a front cross member and a rear cross member extending in the vehicle width direction at a distance in the fore-and-aft direction of the vehicle and connected to the front and rear ends of the pair of side members, and is a suspension cross member that supports a powertrain with the pair of side members and the front cross member and supports suspension arms that support wheels, and is characterized in that, in a side view, a pair of powertrain mounting brackets are provided near the rear ends of the pair of side members, positioned rearward of the rear end of the powertrain and below the rear cross member. In addition, one embodiment of the present invention is characterized in that a stabilizer is provided to connect the suspension arms provided on both sides in the vehicle width direction, and the middle portion of the stabilizer in the vehicle width direction is positioned rearward of the pair of powertrain mounting brackets. Furthermore, one embodiment of the present invention is characterized in that a pair of lower arm brackets are joined to the vehicle fore-and-aft direction middle portions of the pair of side members, and the front ends of the pair of powertrain mount brackets are joined to the rear ends of the pair of lower arm brackets. In addition, one embodiment of the present invention is characterized in that the pair of lower arm brackets have front support pieces and rear support pieces that face each other in the fore-and-aft direction of the vehicle, the front ends of the pair of powertrain mount brackets are joined to the rear support pieces, and the front support pieces and the rear support pieces are connected by a first reinforcement extending in the fore-and-aft direction of the vehicle. In addition, one embodiment of the present invention is characterized in that the front support pieces of the pair of lower arm brackets and both ends of the front cross member are each connected by a second reinforcement extending in the fore-and-aft direction of the vehicle. [Effects of the Invention]

[0006] According to one embodiment of the present invention, a collision load input during a rear collision can be reliably received by a pair of powertrain mount brackets, and the input collision load can be efficiently transmitted to the entire suspension cross member via a pair of side members. This is advantageous in that it can prevent the collision load from being input to the powertrain during a rear collision and protect the powertrain. Furthermore, if the middle portion of the stabilizer in the vehicle width direction is positioned behind a pair of powertrain mounting brackets, the collision load input during a rear-end collision can be reliably absorbed by the middle portion of the stabilizer, and the input collision load can be efficiently transmitted to the entire suspension cross member via the pair of powertrain mounting brackets and a pair of side members, which is more advantageous in protecting the powertrain. Furthermore, when the front ends of a pair of powertrain mounting brackets are joined to the rear ends of a pair of lower arm brackets, the collision load input during a rear-end collision can be reliably absorbed by the pair of lower arm brackets, and the input collision load can be efficiently transmitted to the entire suspension cross member via the pair of side members, which is more advantageous in protecting the powertrain. Furthermore, if the front ends of the pair of powertrain mounting brackets are joined to the rear support pieces and the front support pieces and the rear support pieces are connected by a first reinforcement extending in the fore-and-aft direction of the vehicle, the collision load input during a rear-end collision can be reliably absorbed by the pair of lower arm brackets and the first reinforcement, and the input collision load can be efficiently transmitted to the entire suspension cross member via the pair of side members, which is even more advantageous in protecting the powertrain. Furthermore, if the front support pieces of a pair of rear lower arm brackets and both ends of the front cross member are each connected by a second reinforcement extending in the fore-and-aft direction of the vehicle, the collision load input during a rear-end collision is absorbed not only by the pair of lower arm brackets but also by the second reinforcement and the front cross member, and the input collision load can be efficiently transmitted to the entire suspension cross member via the pair of side members and the front cross member, which is further advantageous in protecting the powertrain. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 2 is a plan view of a suspension cross member according to an embodiment, with the powertrain not shown. [Figure 2] FIG. 2 is a plan view of a suspension cross member according to an embodiment, in which the power train and each suspension arm are not shown. [Figure 3] FIG. 2 is a perspective view of the suspension cross member according to the embodiment, seen from the rear, with the powertrain not shown. [Figure 4] FIG. 2 is a bottom view showing a state in which a powertrain is supported by a suspension cross member according to an embodiment, with the suspension arms not shown. [Figure 5] 1 is a side view of a suspension cross member according to an embodiment, seen from the vehicle width direction, with the suspension arms not shown. FIG. [Figure 6] FIG. 6 is a view taken along the arrow A in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0008] A suspension cross member according to an embodiment of the present invention will now be described with reference to the drawings. In the following drawings, the symbol FR indicates the front of the vehicle, the symbol UP indicates the upper side of the vehicle, and the symbol LH indicates the width direction of the vehicle. As shown in FIGS. 4 and 5, a rear wheel (not shown) is supported by a suspension cross member 10 via a suspension arm 26, and this suspension cross member 10 supports a power train 12 of an electric vehicle. Although not shown, the power train 12 includes a motor, a reducer that reduces the rotational speed of the motor and transmits the rotational speed to the axle, and a converter that supplies driving power to the motor. In this specification, the term "electric vehicle" includes an electric vehicle that uses only a motor as a drive source, a hybrid vehicle, or a plug-in hybrid vehicle (PHEV) that can be externally charged or externally powered.

[0009] As shown in Figures 1 and 2, the suspension cross member 10 is composed of a pair of side members 14, a front cross member 16, a rear cross member 18, and an intermediate cross member 20, each of which has a closed cross-sectional structure with a rectangular cross section. The pair of side members 14, the front cross member 16, the rear cross member 18, and the intermediate cross member 20 provide an arrangement space S for arranging the powertrain 12 inside thereof. The pair of side members 14 extend in the front-rear direction of the vehicle and are spaced apart in the vehicle width direction. The front cross member 16, rear cross member 18, and intermediate cross member 20 extend in the vehicle width direction at intervals in the vehicle's fore-and-aft direction, with the front cross member 16 connecting the front ends of a pair of side members 14, the rear cross member 18 connecting the rear ends of a pair of side members 14, and the intermediate cross member 20 connecting the fore-and-aft middle portions of the pair of side members 14. As shown in FIG. 5, the front cross member 16 extends in the vehicle width direction, passing through the middle of the powertrain 12 in the vertical height direction. As shown in FIG. 6, the rear cross member 18 passes through the middle of the powertrain 12 in the vertical height direction and extends in the vehicle width direction. As shown in FIG. 6, the intermediate cross member 20 has a middle portion that is positioned lower than both end portions, and the middle portion passes below the lower portion 12A of the powertrain 12 and extends in the vehicle width direction.

[0010] As shown in FIGS. 3 and 5, a pair of first powertrain mounting brackets 22 for disposing the powertrain 12 in the disposing space S are provided at locations near the rear ends of the lower portions of the pair of side members 14. The first powertrain mount brackets 22 are provided with powertrain mounts 24 that support both rear sides of the powertrain 12, respectively. As shown in FIG. 5, when the powertrain 12 is disposed in the arrangement space S, the first powertrain mounting bracket 22 is located rearward of the rear end of the powertrain 12 and below the rear cross member 18.

[0011] As shown in FIG. 1, there are five suspension arms 26 supporting the rear wheels, three of which are attached to a pair of side members 14, and the remaining two suspension arms 26 are attached to both ends of the front cross member 16. More specifically, as shown in FIG. 1, each of the pair of side members 14 swingably supports three suspension arms 26, namely, a front upper arm 28, a rear lower arm 30, and a rear upper arm 32, which are aligned from the front to the rear of the vehicle. That is, the tip ends of the front upper arm 28, the rear lower arm 30 and the rear upper arm 32 are swingably supported by wheel support members 38 that rotatably support the wheels, and the base ends of the front upper arm 28, the rear lower arm 30 and the rear upper arm 32 are swingably supported by front upper arm bracket 40, rear lower arm bracket 42 and rear upper arm bracket 44 that are joined to side member 14, as shown in Figures 3 and 5. As shown in FIG. 5, the rear lower arm bracket 42 is joined to the vehicle front-rear direction intermediate portions of the pair of side members 14, and has a front support piece 42A and a rear support piece 42B that face each other in the vehicle front-rear direction. The front ends 22A of the pair of first powertrain mounting brackets 22 are joined to the rear support pieces 42B, and therefore the front ends 22A of the pair of first powertrain mounting brackets 22 are joined to the rear ends of the pair of rear lower arm brackets 42. Furthermore, the front support piece 42A and the rear support piece 42B are connected by a first reinforcement 46 that extends in the front-rear direction of the vehicle.

[0012] As shown in Figures 1, 3, and 5, frame mounts 48 are provided at both ends of the front cross member 16 to support a pair of side frames (not shown) that constitute the body frame members from below, and frame mounts 48 are provided at both ends of the rear cross member 18 to support a pair of side frames from below. As shown in Figures 1 and 4, second powertrain mounting brackets 50 are provided at locations near both ends of the front cross member 16 to support both front sides of the powertrain 12 arranged in the arrangement space S. The second powertrain mount brackets 50 are provided with powertrain mounts 25 that support both front sides of the powertrain 12, respectively. As shown in Figures 5 and 6, when the powertrain 12 is placed in the placement space S and supported by the powertrain mounts 24, 25, the lower part 12A of the powertrain 12 protrudes downward below the underside of the rear cross member 18.

[0013] As shown in FIG. 1, the remaining two suspension arms 26 are swingably supported at both ends of the front cross member 16. These suspension arms 26 are a first toe control arm 34 and a second toe control arm 36, which are arranged at the front and rear of the vehicle. That is, the tips of the first and second toe control arms 34, 36 are swingably supported by the wheel support member 38, and the base ends of the first and second toe control arms 34, 36 are swingably supported by toe control arm brackets 52 joined to both ends of the front cross member 16, as shown in Figures 4 and 5.

[0014] Furthermore, as shown in FIGS. 3 and 5, a stabilizer 54 is provided that connects the pair of rear upper arms 32 to suppress rolling of the vehicle body. An intermediate portion 54A of the stabilizer 54 in the vehicle width direction extends linearly in the vehicle width direction and is disposed behind the pair of first powertrain mount brackets 22. In this embodiment, as shown in FIG. 3, both ends of the vehicle width direction middle portion 54A of the stabilizer 54 are swingably supported by bearing members 56 provided at the rear ends of a pair of first powertrain mounting brackets 22.

[0015] As shown in FIG. 5, the front support pieces 42A of the pair of rear lower arm brackets 42 and both ends of the front cross member 16 are connected to each other by second reinforcements 58 extending in the vehicle longitudinal direction.

[0016] Next, with reference to FIG. 5, a case where a rear collision occurs in which an object (barrier) BL collides with the rear of the vehicle will be described. When a rear-end collision occurs, the upper part of the object BL collides with the rear cross member 18, and the collision load is received by the rear cross member 18. The collision load received by the rear cross member 18 is transmitted from the rear cross member 18 to the front cross member 16 via a pair of side members 14, and is also transmitted from the four frame mounts 48 on the rear cross member 18 and front cross member 16 to a pair of side frames not shown. At this time, the upper part of the object BL collides with the rear cross member 18 and is deformed rearward, so that the upper part of the object BL is prevented from interfering with the rear part of the powertrain 12.

[0017] Meanwhile, the lower part of the object BL collides with the middle part 54A of the stabilizer 54, and the collision load is received by the pair of first powertrain mount brackets 22, the strength and rigidity of which is ensured by the stabilizer 54. The collision load received by the pair of first powertrain mount brackets 22 is transmitted from the pair of first powertrain mount brackets 22 to the pair of side members 14. In this embodiment, the stabilizer 54 is supported by a pair of first powertrain mount brackets 22 via bearing members 56, and therefore the collision load is transmitted from the stabilizer 54 to the pair of first powertrain mount brackets 22 via the bearing members 56. Furthermore, if the intermediate portion 54A of the stabilizer 54 is not supported by the pair of first powertrain mount brackets 22, the intermediate portion 54A of the stabilizer 54 that receives the collision load will be displaced forward and come into contact with the rear ends of the pair of first powertrain mount brackets 22, and the collision load will naturally be transmitted from the stabilizer 54 to the pair of first powertrain mount brackets 22.

[0018] Furthermore, the collision load transmitted to the pair of first powertrain mounting brackets 22 is transmitted from the front ends 22A of the pair of first powertrain mounting brackets 22 to the rear support piece 42B, which is the rear end of the pair of rear lower arm brackets 42, and then transmitted to the front support piece 42A via the first reinforcement 46. The collision load transmitted to the rear support piece 42B and the front support piece 42A is also transmitted to the pair of side members 14. The collision load transmitted to the front support piece 42A is transmitted to both ends of the front cross member 16 via the second reinforcement 58, and then transmitted from the two frame mounts 48 of the front cross member 16 to a pair of side frames not shown. At this time, the lower part of the object BL is deformed rearward by colliding with a pair of first powertrain mounting brackets 22 via the stabilizer 54, so that the lower part of the object BL slips under the rear cross member 18 and is prevented from interfering with the lower part 12A of the powertrain 12 protruding downward from the underside of the rear cross member 18. Therefore, the input of a collision load to the powertrain 12 during a rear collision is suppressed, and the powertrain 12 is protected.

[0019] According to this embodiment, in a side view, a pair of first powertrain mounting brackets 22 are provided near the rear ends of a pair of side members 14, located rearward of the rear end of the powertrain 12 and below the rear cross member 18. Therefore, the collision load input during a rear-end collision can be reliably received by the pair of first powertrain mounting brackets 22, and the input collision load can be efficiently transmitted to the entire suspension cross member 10 via the pair of side members 14. Therefore, it is possible to suppress the input of a collision load to the powertrain 12 in the event of a rear collision, which is advantageous in terms of protecting the powertrain 12.

[0020] In this embodiment, an intermediate portion 54A of the stabilizer 54 in the vehicle width direction is disposed behind the pair of first powertrain mounting brackets 22. Therefore, the collision load input during a rear-end collision can be reliably received by the middle portion 54A of the stabilizer 54, and the input collision load can be efficiently transmitted to the entire suspension cross member 10 via a pair of first powertrain mounting brackets 22 and a pair of side members 14. This is more advantageous in suppressing the input of a collision load to the powertrain 12 during a rear collision, and is more advantageous in protecting the powertrain 12.

[0021] In this embodiment, the front ends 22A of the pair of first powertrain mounting brackets 22 are joined to the rear ends of the pair of rear lower arm brackets . Therefore, the collision load input during a rear collision can be reliably received by the pair of rear lower arm brackets 42, and the input collision load can be efficiently transmitted to the entire suspension cross member 10 via the pair of side members 14. This is more advantageous in suppressing the input of a collision load to the powertrain 12 during a rear collision, and is more advantageous in protecting the powertrain 12.

[0022] In addition, in this embodiment, the front ends 22A of the pair of first powertrain mounting brackets 22 are joined to the rear support piece 42B, and the front support piece 42A and the rear support piece 42B are connected by a first reinforcement 46 extending in the fore-and-aft direction of the vehicle. Therefore, the collision load input during a rear-end collision can be reliably received by the pair of rear lower arm brackets 42 and the first reinforcement 46, and the input collision load can be efficiently transmitted to the entire suspension cross member 10 via the pair of side members 14. This is more advantageous in suppressing the input of a collision load to the powertrain 12 during a rear collision, and is more advantageous in protecting the powertrain 12.

[0023] In addition, in this embodiment, the front support pieces 42A of the pair of rear lower arm brackets 42 and both ends of the front cross member 16 are connected to each other by second reinforcements 58 extending in the vehicle longitudinal direction. Therefore, the collision load input during a rear-end collision is absorbed not only by the pair of rear lower arm brackets 42, but also by the second reinforcement 58 and the front cross member 16, and the input collision load can be efficiently transmitted to the entire suspension cross member 10 via the pair of side members 14 and the front cross member 16. This is more advantageous in suppressing the input of a collision load to the powertrain 12 during a rear collision, and is more advantageous in protecting the powertrain 12.

[0024] 10 Suspension cross member 12 Powertrain 12A Lower 14 Side member 16 Front cross member 18 Rear cross member 20 Intermediate cross member 22 First powertrain mounting bracket (powertrain mounting bracket) 22A rear end 24, 25 Powertrain mount 26 Suspension arm 28 Front upper arm 30 Rear lower arm (lower arm) 32 Rear upper arm 34 First toe control arm 36 Second toe control arm 38 Wheel support member 40 Front upper arm bracket 42 Rear lower arm bracket (lower arm bracket) 42A Front support piece 42B Rear support piece 44 Rear upper arm bracket 46 First Reinforcement 48 Frame Mount 50 Mounting bracket for second powertrain 52 Toe control arm bracket 54 Stabilizer 54A Middle section 56 Bearing parts 58 Second Reinforcement S Placement space BL Object (Barrier)

Claims

1. a pair of side members extending in the longitudinal direction of the vehicle at a distance in the vehicle width direction, and a front cross member and a rear cross member extending in the longitudinal direction of the vehicle at a distance in the vehicle width direction and connected to front end portions and rear end portions of the pair of side members, wherein the pair of side members and the front cross member support a power train and support suspension arms that support wheels, a pair of powertrain mount brackets are provided in the vicinity of rear ends of the pair of side members, the mount brackets being positioned rearward of the rear end of the powertrain and below the rear cross member in a side view; A suspension cross member characterized by:

2. a stabilizer is provided to connect the suspension arms provided on both sides in the vehicle width direction; a middle portion of the stabilizer in the vehicle width direction is disposed rearward of the pair of powertrain mounting brackets; 2. The suspension cross member according to claim 1.

3. a pair of lower arm brackets are joined to intermediate portions of the pair of side members in the vehicle front-rear direction, front ends of the pair of powertrain mount brackets are joined to rear ends of the pair of lower arm brackets; 2. The suspension cross member according to claim 1.

4. the pair of lower arm brackets have front and rear support pieces that face each other in the vehicle front-rear direction, front ends of the pair of powertrain mount brackets are joined to the rear support piece; The front support piece and the rear support piece are connected by a first reinforcement extending in the front-rear direction of the vehicle.

4. The suspension cross member according to claim 3.

5. The front support pieces of the pair of lower arm brackets and both ends of the front cross member are respectively connected by second reinforcements extending in the vehicle front-rear direction.

5. The suspension cross member according to claim 4.

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