Subframe

Abstract

The present invention provides a subframe with high rigidity. The subframe includes a main body (10) and a body support portion (20) that supports the main body (10) on a body. The body support portion (20) includes a front wall portion (21) extending along a first surface (S1) perpendicular to the front-rear direction at the front end, a rear wall portion (22) extending along a second surface (S2) perpendicular to the front-rear direction at the rear end, and a central portion (23) connecting the front wall portion (21) and the rear wall portion (22) and extending along a third surface (S3) intersecting the first surface (S1) and the second surface (S2). The central portion (23) has an upper rib (24) protruding upward along a fourth surface (S4) perpendicular to the third surface (S3), and a lower rib (25) protruding downward along a fifth surface (S5) perpendicular to the third surface (S3).

Description

Technical Field

[0001] The present invention relates to a subframe. Background Art

[0002] Conventionally, there is known a suspension element fixed to the lower portion of a vehicle body (for example, refer to Japanese Patent Application Laid-Open No. 2005-59813). Summary of the invention

[0003] However, the suspension element described in Japanese Patent Application Laid-Open No. 2005-59813 has room for improvement in rigidity.

[0004] An object of the aspects of the present invention is to provide a subframe having high rigidity.

[0005] A subframe of a first embodiment of the present invention includes a main body portion and a vehicle body support portion that supports the main body portion on a vehicle body, the vehicle body support portion includes a front wall portion that extends along a first surface perpendicular to the front-rear direction at a front end, a rear wall portion that extends along a second surface perpendicular to the front-rear direction at a rear end, and a central portion that connects the front wall portion and the rear wall portion and extends along a third surface that intersects the first surface and the second surface, the central portion having an upper rib that protrudes upward along a fourth surface perpendicular to the third surface, and a lower rib that protrudes downward along a fifth surface perpendicular to the third surface.

[0006] According to this structure, the vehicle body support portion includes a front wall portion extending along a first surface perpendicular to the front-rear direction at the front end, a rear wall portion extending along a second surface perpendicular to the front-rear direction at the rear end, and a central portion connecting the front wall portion and the rear wall portion and extending along a third surface intersecting the first surface and the second surface. In addition, the central portion includes an upper rib protruding upward along a fourth surface perpendicular to the third surface, and a lower rib protruding downward along a fifth surface perpendicular to the third surface. Thus, while maintaining the positional relationship between the vehicle body connection portion at the upper end of the vehicle body support portion and the main body portion, the bending rigidity of the vehicle body support portion can be ensured, and at the same time, the neutral axis (or centroid) of the cross section of the vehicle body support portion is located close to the main body and as far downward as possible.

[0007] Therefore, the natural vibration frequency of the entire subframe in the torsion mode with the vehicle body connection portion at the upper end of the vehicle body support portion as a fulcrum can be increased, that is, the torsion rigidity of the subframe can be increased. As a result, a subframe with high rigidity can be provided. In addition, by moving the position of the central portion, the natural vibration frequency in the torsion mode can be easily adjusted, and the degree of freedom in designing the subframe can be increased.

[0008] In the second aspect, the subframe may include a suspension connection portion to which a suspension device that supports an axle is connected, and the front wall portion may be continuous to the suspension connection portion along the same plane.

[0009] According to this structure, the front wall portion is continuous to the suspension connection portion along the same plane. This can improve the rigidity of the suspension connection portion and the rigidity of the vehicle body support portion.

[0010] In the third aspect, the vehicle body support portion may include a boss portion, the boss portion having a seat surface for a connection member connected to the vehicle body provided at a lower portion thereof, and the central portion may be located below the seat surface.

[0011] According to this structure, the vehicle body support portion has a boss portion, the boss portion is provided with a seat surface of a connecting member connected to the vehicle body at the lower portion, and the central portion is located below the seat surface. As a result, the neutral axis can be located close to the main body portion. As a result, the positional relationship between the vehicle body connecting portion at the upper end of the vehicle body support portion and the main body portion can be maintained, and at the same time, the bending rigidity of the vehicle body support portion and the rigidity of the subframe can be improved.

[0012] In the fourth aspect, the vehicle body support portion may include a reinforcement wall extending from an upper end of the central portion to the boss portion.

[0013] According to this structure, the vehicle body support portion has the reinforcing wall extending from the upper end of the central portion to the boss portion. This can further improve the rigidity of the vehicle body connecting portion and the rigidity of the vehicle body support portion.

[0014] In the fifth aspect, the main body portion may include a main body side wall extending in the front-rear direction along a plane perpendicular to the vehicle width direction, and the rear wall portion may protrude outward from the main body side wall.

[0015] According to this structure, the main body has main body side walls extending in the front-rear direction along a plane perpendicular to the vehicle width direction, and the rear wall protrudes outward from the main body side walls. This can further improve the rigidity of the vehicle body support portion and the rigidity of the subframe.

[0016] In the sixth aspect, the main body portion may include a main body rib protruding downward, and at least one of the front wall portion and the rear wall portion may be continuous to the main body rib.

[0017] According to this structure, the main body has a main body rib protruding downward, and at least one of the front wall and the rear wall is continuous to the main body rib. This can further improve the rigidity of the vehicle body support portion and the rigidity of the subframe.

[0018] According to the aspects of the present invention, a subframe having high rigidity can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1This is a perspective view of a subframe according to an embodiment of the present invention as viewed from the front and above.

[0020] Figure 2 This is a perspective view of a subframe according to one embodiment as viewed from the front and bottom.

[0021] Figure 3 is a top view of a subframe according to one embodiment.

[0022] Figure 4 is a bottom view of a subframe according to one embodiment.

[0023] Figure 5 This is a perspective view of a left vehicle body support portion according to one embodiment as viewed from the front and above.

[0024] Figure 6 This is a perspective view of a left vehicle body support portion according to one embodiment as viewed from the rear lower side.

[0025] Figure 7 yes Figure 3 AA line section stereogram. DETAILED DESCRIPTION

[0026] Hereinafter, a subframe 100 according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, arrow FR indicates the front of the vehicle, arrow RB indicates the rear of the vehicle, arrow UP indicates the top of the vehicle, arrow DW indicates the bottom of the vehicle, arrow L indicates the left of the vehicle, and arrow R indicates the right. The left-right direction of the vehicle is sometimes referred to as the vehicle width direction. The center side of the vehicle in the vehicle width direction is sometimes referred to as the inner direction, and the direction away from the center side of the vehicle in the vehicle width direction is sometimes referred to as the outer direction. The subframe 100 has a substantially left-right symmetrical structure. Therefore, in the following description, the left and right components are sometimes labeled with the same symbols.

[0027] Figure 1 This is a perspective view of a subframe according to an embodiment of the present invention as viewed from the front and above. Figure 2 This is a perspective view of a subframe according to one embodiment as viewed from the front and bottom. Figure 3 FIG. 1 is a top view of a subframe 100 according to one embodiment. Figure 4 FIG. 1 is a bottom view of a subframe 100 according to one embodiment.

[0028] (Subframe)

[0029] like Figure 1 to Figure 4 As shown, the subframe 100 is a member that forms a part of the frame of the vehicle together with a vehicle body (not shown). The subframe 100 is provided below the vehicle body.

[0030] The subframe 100 includes a main body 10 and a vehicle body support 20 that supports the main body 10 on the vehicle body. The main body 10 and the vehicle body support 20 are integrally formed by, for example, die casting. The main body 10 and the vehicle body support 20 are made of, for example, an alloy of non-ferrous metal such as aluminum.

[0031] (Main body)

[0032] The main body 10 is supported by the vehicle body via the vehicle body support portion 20 .

[0033] The main body 10 includes a suspension connection portion 12 for connecting a suspension device (not shown) supporting an axle (not shown) and a torsion bar support portion 13. Vehicle components such as a stabilizer and a steering gear box are appropriately arranged in a space between the main body 10 and the vehicle body.

[0034] The main body portion 10 has a main body side wall 11 extending in the front-rear direction along a plane perpendicular to the vehicle width direction. This can improve the torsional rigidity and bending rigidity of the subframe 100.

[0035] The main body 10 has a main body rib 10R protruding downward. The main body rib 10R is a plate-like body, and a plurality of main body ribs 10R may be provided on the main body 10. The plurality of main body ribs 10R may be arranged along planes having normal lines in different directions, or may be arranged in a manner intersecting each other. Thus, the torsional rigidity and bending rigidity of the subframe 100 may be improved.

[0036] The suspension connection part 12 supports the suspension arm (not shown) of the suspension device through a hinge. The suspension connection part 12 is composed of two plate-like bodies that are bifurcated from the main body 10, for example. The two plate-like bodies each have a hole for locking the shaft constituting the hinge. The suspension connection part 12 can be provided with two pairs on the left and right sides of the main body 10.

[0037] <Torsion bar support>

[0038] The torsion bar support portion 13 supports a torsion bar TR connected to a power unit (not shown). One end of the torsion bar TR is connected to the subframe 100 by a hinge via a bushing (not shown). The other end of the torsion bar TR is connected to a power unit such as an engine. The torsion bar support portion 13 is arranged at the center of the body portion 10 in the vehicle width direction.

[0039] Specifically, the torsion bar support portion 13 protrudes upward from the upper surface of the main body 10. The torsion bar support portion 13 forms a space capable of accommodating one end of the torsion bar TR. The torsion bar support portion 13 includes: a top plate 13W that supports one end of the shaft P that supports the torsion bar TR; and a side plate 13V. It should be noted that the shaft P constitutes a hinge that supports the torsion bar TR so that it can swing freely.

[0040] The top plate 13W is a plate-like body having a substantially horizontal surface along the upper surface of the main body 10. The top plate 13W is located above the upper surface of the main body 10. The top plate 13W has a space at the bottom that can accommodate the torsion bar TR. The top plate 13W is formed integrally with the main body 10 via a side plate 13V extending upward from the main body 10. The top plate 13W has a first shaft support portion 131 substantially in the center when viewed from above. A reinforcing plate 30 is provided below the top plate 13W to separate the accommodating space for the torsion bar TR and the lower opening portion A2. The first shaft support portion 131 provided on the top plate 13W supports one end of the shaft P. The second shaft support portion 132 provided on the reinforcing plate 30 supports the other end of the shaft P.

[0041] (Body support part)

[0042] Figure 5 This is a perspective view of the left vehicle body support portion 20A according to one embodiment as viewed from the front upper side. Figure 6 This is a perspective view of the left vehicle body support portion 20A according to one embodiment as viewed from the rear lower side. Figure 7 yes Figure 3 AA line section stereogram.

[0043] The vehicle body support 20 is a portion that supports the main body 10 on the vehicle body. The vehicle body support 20 includes a left vehicle body support 20A that is arranged on the left side of the main body 10 and supported on the left side of the vehicle body, and a right vehicle body support 20B that is arranged on the right side of the main body 10 and supported on the right side of the vehicle body. The left vehicle body support 20A and the right vehicle body support 20B are separated in the vehicle width direction and arranged symmetrically.

[0044] The left body support 20A and the right body support 20B extend upward. Specifically, the left body support 20A and the right body support 20B extend outwardly in a manner that they separate from each other as they go upward. The subframe 100 (main body 10) is installed along the vehicle width direction of the vehicle body by the left body support 20A and the right body support 20B in a state where a space is formed between the vehicle body and the main body 10. It should be noted that in the subframe 100, the body support 20 is not limited to the left body support 20A and the right body support 20B, and may further include other body support parts.

[0045] The vehicle body support portion 20 has a vehicle body connection portion 40 connected to the vehicle body at the upper portion. The vehicle body connection portion 40 has a boss portion 42, and the boss portion 42 has a seat surface 41 for a connection member (not shown) such as a pin or a bolt connected to the vehicle body at the lower portion. In this way, since the vehicle body support portion 20 has the boss portion 42 at the vehicle body connection portion 40, the rigidity of the vehicle body connection portion 40 connecting the vehicle body and the vehicle body support portion 20 can be improved, and the subframe 100 can be reliably fixed to the vehicle body.

[0046] In detail, Figure 7 As shown in FIG. 1 , the vehicle body support portion 20 includes: a front wall portion 21 extending along a first surface S1 perpendicular to the front-rear direction at the front end; a rear wall portion 22 extending along a second surface S2 perpendicular to the front-rear direction at the rear end; and a center portion 23 connecting the front wall portion 21 and the rear wall portion 22 and extending along a third surface S3 intersecting the first surface S1 and the second surface S2. In addition, the center portion 23 includes: an upper rib 24 protruding upward along a fourth surface S4 perpendicular to the third surface S3; and a lower rib 25 protruding downward along a fifth surface S5 perpendicular to the third surface S3. Thus, while maintaining the positional relationship between the vehicle body connection portion 40 at the upper end of the vehicle body support portion 20 and the main body 10, the bending rigidity of the vehicle body support portion 20 can be ensured, and at the same time, the neutral axis (or centroid) of the cross section of the vehicle body support portion 20 can be located close to the main body 10 and as far as possible below. Therefore, the natural vibration frequency of the entire subframe 100 in the torsion mode with the vehicle body connecting portion 40 at the upper end of the vehicle body supporting portion 20 as a fulcrum can be increased, that is, the torsion rigidity of the subframe 100 can be increased. As a result, a subframe 100 with high rigidity can be provided. In addition, by moving the position of the center portion 23, the natural vibration frequency in the torsion mode can be easily adjusted, and the degree of freedom in designing the subframe 100 can be increased.

[0047] It should be noted that the third surface S3 may intersect the first surface S1 and the second surface S2 perpendicularly. It should be noted that the fourth surface S4 and the fifth surface S5 may be on the same plane. Figure 7 In the cross section shown, the upper rib 24 and the lower rib 25 can be continuous in a straight line in the vertical direction. It should be noted that the front wall portion 21, the rear wall portion 22, the central portion 23, the upper rib 24 and the lower rib 25 can be different or the same in thickness as long as they are along the imaginary plane from the first surface S1 to the fifth surface S5 as described above.

[0048] Here, the front wall portion 21 is continuous to the suspension connection portion 12 along the same plane. Figure 7 As shown, the plate-like body constituting the suspension connection portion 12 extends along the first surface S1 and is continuously connected to the front wall portion 21 in the vertical direction. This can improve the rigidity of the suspension connection portion 12 and the rigidity of the vehicle body support portion 20.

[0049] like Figure 6 As shown, the center portion 23 is located below the seat surface 41 provided on the boss portion 42. As a result, the neutral axis can be located close to the main body 10. As a result, the positional relationship between the body connecting portion 40 located at the upper end of the body support portion 20 and the main body 10 can be maintained, and at the same time, the bending rigidity of the body support portion 20 and the rigidity of the subframe 100 can be improved.

[0050] like Figure 5 and Figure 6 As shown in FIG. 1 , the vehicle body support portion 20 has a reinforcing wall 50 extending from the upper end of the central portion 23 to the boss portion 42. The reinforcing wall 50 is provided in the entire range between the upper end of the upper rib 24 or the lower rib 25 and the front wall portion 21 and the rear wall portion 22. The reinforcing wall 50 may be a plate-like body extending along a surface perpendicular to the first surface S1, the second surface S2, the fourth surface S4, or the fifth surface S5. The reinforcing wall 50 may also be a plate-like body extending along a surface parallel to the axis of the boss portion 42. Thus, the rigidity of the vehicle body connection portion 40 and the rigidity of the vehicle body support portion 20 can be further improved.

[0051] like Figure 6 and Figure 7 As shown, the rear wall 22 protrudes outward from the main body side wall 11 of the main body 10. The rear wall 22 extends continuously from the rear end of the vehicle body support 20 to the outside of the main body 10 in the vertical direction. Thus, the rigidity of the vehicle body support 20 and the rigidity of the subframe 100 can be further improved.

[0052] like Figure 2 and Figure 6 As shown in FIG. 1 , at least one of the front wall portion 21 and the rear wall portion 22 is continuous to the main rib 10R of the main body portion 10. Figure 2 and Figure 6 As shown, both the front wall portion 21 and the rear wall portion 22 may be continuous to the main body rib 10R of the main body portion 10. This can further improve the rigidity of the vehicle body support portion 20 and the rigidity of the subframe 100.

[0053] It should be noted that the technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

[0054] For example, the suspension connection portion 12 may also serve as the vehicle body support portion 20. That is, the suspension connection portion 12 may be connected to the suspension device and supported by the vehicle body by fastening the suspension connection portion 12, a part of the suspension device, and a part of the vehicle body together with an appropriate fastener.

[0055] In addition, for example, in the subframe 100, the vehicle body support 20 is not limited to the left vehicle body support 20A and the right vehicle body support 20B, but may further include a plurality of vehicle body supports. In this case, any one of the vehicle body supports may have the features of the vehicle body support 20 of the above-described embodiment.

[0056] Furthermore, the components in the above-described embodiments may be appropriately replaced with well-known components without departing from the spirit of the present invention, and the above-described modified examples may be appropriately combined.

Claims

1. A subframe, wherein: The subframe comprises: the main body; and The vehicle body support portions are separated in the vehicle width direction of the main body portion and are disposed symmetrically on both sides, and extend outwardly in an inclined manner so as to separate from each other as they go upward, The vehicle body support portion comprises: A front wall portion extending at the front end along a first surface perpendicular to the front-to-rear direction; A rear wall portion extending at the rear end along a second surface perpendicular to the front-rear direction; A central portion disposed between the front wall portion and the rear wall portion, connecting the front wall portion and the rear wall portion and extending along a third surface perpendicularly intersecting the first surface and the second surface; an upper rib disposed between the front wall portion and the rear wall portion and protruding upward from the central portion along a fourth surface perpendicular to the third surface; as well as a lower rib disposed between the front wall portion and the rear wall portion and protruding downward from the central portion along a fifth surface perpendicular to the third surface; The upper rib and the lower rib are connected in a straight line along the vertical direction. The subframe includes a suspension connection portion for connecting a suspension device that supports the axle. The front wall portion is continuous to the suspension connection portion along the same plane, The vehicle body support portion includes a boss portion, and the boss portion is provided with a seat surface of a connecting member connected to the vehicle body at a lower portion. The central portion is located below the seat surface.

2. The subframe according to claim 1, wherein: The vehicle body support portion has a reinforcement wall extending from an upper end of the central portion to the boss portion.

3. The subframe according to claim 1, wherein: The main body portion includes a main body side wall extending in the front-rear direction along a plane perpendicular to the vehicle width direction, and the rear wall portion protrudes outward from the main body side wall.

4. The subframe according to claim 1, wherein: The main body has a main rib protruding downward. At least one of the front wall portion and the rear wall portion is continuous to the main body rib.

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