JP2002337723A - Sub frame for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sub frame for a vehicle in which an end of a member is hardly deformed at a connection portion between the end of the member constituting the sub frame and a joint part, rigidity of the end of the member is improved and manufacture is easy. SOLUTION: At a joint part 20 connected to the end of a cross member 4 constituting the sub frame, a flat-state mounting face part 24 is formed at a part of the outer circumferential face of the joint part 20. The mounting face part 24 is brought into contact with the end face of the cross member 4, and as the mounting face part 24 is welded and connected to the end of the cross member 4 in the state where a side 25a of a projection 25 for positioning formed at the edge of the mounting face part 24 is brought into contact with the outer circumferential face of the cross member 4 (W is a welded part), the joint part 20 is connected to the cross member 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a subframe for a vehicle such as an automobile, and more particularly, to a metal subframe having a joint connected to another frame.

[0002] In this specification, the term "aluminum" is used to include its alloy.

[0003]

2. Description of the Related Art In an automobile, for example, a suspension device, a differential device, a steering device, an engine and the like are generally supported by a subframe.

As this type of subframe, for example,
A pair of right and left cross members extending in the left-right direction of the vehicle body and a pair of left and right side members extending in the front-rear direction of the vehicle body and extending between the two cross members to connect the two cross members are provided. Is generally known in the shape of a square.

In this subframe, generally, the end of the cross member (100) (or the end of the side member)
As shown in FIGS. 6A and 6B, a joint (120) connected to a main frame (not shown) is formed on the main frame. The structure of the cross member (100) will be briefly described. The cross member (100) is formed of an iron pipe material having a substantially square cross section. A circular hole (101) is stamped and formed in the outer peripheral surface of the end of the cross member (100), and a metal part having a hollow portion as a bush mounting hole (122) is formed in the hole (101). Cylindrical boss (123) is fitted tightly. Then, in this fitted state, the boss (123) is welded over the entire periphery of the hole (101) (W 'is a welded portion), whereby the bracket (123) is fixed. A bush (B ′) having a rubber elastic portion is press-fitted into the bush mounting hole (122) of the boss (123) as shown in FIG.

[0006]

However, the conventional subframe having the above configuration has the following disadvantages. That is, since the hole (101) into which the boss (123) is fitted is formed by punching, there is a problem that the end of the cross member (100) is deformed during the punching. Of course, since such holes (101) must be formed on the outer peripheral surface of the end of the cross member (100), the production is troublesome, and as a result, the production cost is high. Was.

Further, since the boss (123) is welded and fixed over the entire circumference, the inner diameter of the boss (123) (ie, the hole diameter of the bush mounting hole (122)) due to the thermal distortion caused by welding.
Of the bush (B '), and the mounting operation becomes difficult. Further, in such a mounting structure of the boss (123), when a load is applied to the bush (B '), a portion of the cross member (100) in the vicinity of the boss (123) may be deformed. Cross members for (100)
Therefore, the rigidity of the end of the cross member (100) must be improved by increasing the thickness of the cross member. As a result, there is a problem that the weight of the cross member (100) increases. Further, since the end opening of the cross member (100) is kept open, there is a possibility that muddy water or the like in a water pool may enter from the opening.

The present invention has been made in view of the above-mentioned technical background, and a main object of the present invention is to enable a joint portion to be easily connected to an end portion of a member constituting a sub-frame, An object of the present invention is to provide a vehicle sub-frame in which the rigidity of the end of a member to which the parts are connected is improved.

[0009]

In order to achieve the above object, the present invention provides at least one cross member extending in the left-right direction of the vehicle body and at least one side member extending in the front-rear direction of the vehicle body. And a joint body connected to an end of at least one of a cross member and a side member in the sub frame body. For the sub-frame, the joint portion has a mounting surface portion attached to the sub-frame main body, by attaching the mounting surface portion to the end surface of the member,
The joint part is connected (claim 1).

[0010] In this vehicle subframe, the end of the member is restrained by joining the mounting surface to the end face, and as a result, the rigidity of the end of the member is improved. Become. In other words, even if the thickness of the end portion of the member is not increased, the rigidity of the end portion of the member is improved, so that the weight of the subframe can be reduced. In addition, since the joint can be joined to the end of the member without directly joining most of the joint, a predetermined portion of the joint (the bushing) which may occur with the joint of the joint is formed. Since the dimensional change of the mounting portion and the like can be prevented or suppressed, and there is no need to form a hole into which a boss or the like is fitted on the outer peripheral surface of the member end portion,
The manufacturing cost of the subframe can be reduced.

In the above-mentioned vehicle sub-frame, it is preferable that the sub-frame main body is formed by connecting a pair of front and rear cross members and a pair of left and right side members to each other in a substantially rectangular shape. (Claim 2).

In this case, the pair of front and rear cross members and the pair of left and right side members are connected to each other in a substantially rectangular shape, so that the strength of the subframe main body is improved.

In the above vehicle subframe, the member to which the joint portion is connected is formed of a hollow extruded material having a hollow portion penetrating in the extrusion direction, and an end opening of the member is formed by a mounting surface portion. It is preferable that the mounting surface is joined to the end surface of the member in the closed state (claim 3).

In this case, since the member to which the joint is connected is formed of a hollow extruded material, the weight of the subframe can be reduced, and the member can be manufactured efficiently. As a result, the manufacturing cost of the subframe can be further reduced.

Further, by attaching the mounting surface to the member end in a state where the end opening of the member is closed by the mounting surface, the rigidity of the end of the member is further improved. Intrusion of muddy water and the like in the puddle can be prevented.

In the vehicle sub-frame, it is preferable that the joint portion is formed of a hollow extruded material having a bush mounting hole penetrating in a pushing direction.

In this case, since the joint is formed from a hollow extruded material having a bush mounting hole penetrating in the extrusion direction, the joint can be manufactured efficiently.
Accordingly, the manufacturing cost of the subframe can be further reduced.

In the vehicle sub-frame, it is preferable that the cross member and the side member are connected to each other in a substantially orthogonal state.

In this case, since the cross member and the side member are connected to each other in a substantially orthogonal state, the strength of the subframe main body is improved.

[0020] In the vehicle sub-frame, it is preferable that the cross member, the side member, and the joint are all formed of a hollow extruded material.

In this case, since the cross member, the side member, and the joint are all formed of a hollow extruded material, all of these members can be manufactured efficiently, thereby reducing the manufacturing cost of the subframe. Can be lowered even further, and a lightweight subframe can be manufactured.

In the above-described vehicle sub-frame, the mounting surface of the joint abuts against an end surface of the member, and a positioning protrusion formed on a part of the mounting surface on the outer or inner peripheral surface of the member. Is desirably joined to the member in a state where the side surfaces of the members are in contact with each other (claim 7).

With this arrangement, when connecting the joint to the end of the member, the joint can be easily positioned. As a result, the work of connecting the joint portion to the end of the member can be easily performed, and the manufacturing cost of the subframe can be further reduced.

[0024]

Next, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a vehicle sub-frame is shown as a vehicle sub-frame.

In FIG. 1, (1) is an automobile sub-frame of this embodiment. This subframe (1)
As shown in FIG. 4, is used as a rear sub-frame installed at the rear part of the body of a 4WD vehicle, and is disposed near and above the differential device (40) to support the differential device (40). It is for.

The main body (10) of the subframe (1) is
As shown in FIGS. 1 and 4, a pair of front and rear rod-shaped aluminum cross members (2F) extending in the left-right direction of the vehicle body.
(2R) and a pair of right and left rod-shaped aluminum side members that extend in the front-rear direction of the vehicle body and are connected between the two cross members (2F) and (2R) and are installed between both cross members (2F) and (2R). (6) By (6), it is formed in a substantially rectangular shape in plan view.

In this subframe body (10), the front cross member (2F) and the left and right side members (6)
They are connected to each other in a substantially orthogonal state. Similarly, the rear cross member (2R) and the left and right side members (6) are connected to each other in a substantially orthogonal state.

As shown in FIG. 1, the front cross member (2F) has a substantially middle portion bent in a substantially arc shape so as not to hit the propeller shaft (42). On the other hand, the left and right side members (6), (6) have substantially front halves bent in a substantially arc shape so as not to hit the rear axle (45). In addition,
In FIG. 4, reference numeral (47) denotes left and right rear wheels.

The rear cross member (2R) includes a central cross member (3) disposed at a longitudinally intermediate portion of the rear cross member (2R), and a left and right end portion of the central cross member (3). And a left cross member (4) and a right cross member (4) fixedly connected by welding.

As shown in FIG. 1, a bracket (15) attached to the front of the housing (41) of the differential device (40) is provided on the lower surface of the front cross member (2F).
(15) is provided so as to protrude downward. Brackets (11) attached to links (not shown) of the rear suspension device are provided on the upper and lower surfaces of each side member (6).
(14) is provided. Also, rear cross member (2R)
The lower surface of the center cross member (3)
1) Brackets (12) and (12) attached to the rear part are provided in a downwardly projecting shape. Further, the center cross member (3) is provided with two circular bush mounting holes (13) (13) into which bushes (not shown) connected to the rear part of the housing (41) are mounted. ing.

In the rear cross member (2R), both the right cross member (4) and the left cross member (4) have hollow portions penetrating in the pushing direction (length direction) as shown in FIG. It is formed of an aluminum hollow extruded material having a substantially Japanese character cross section having (4a). In the hollow part (4a) of the hollow extruded material, a reinforcing partition wall part (4b) integrally formed with the peripheral wall part is arranged so as to extend in the length direction.
A joint (20) is fixedly connected to an end of the right cross member (4) and an end of the left cross member (4) by welding. The connection structure of each joint (20) will be described later. As shown in FIG. 5, the left and right joints (20) are fixed to left and right rear frames (main frames, 8) fixed to a floor plate (7) of a luggage compartment as a body in a manner extending in the front-rear direction. They are connected via a bush (B). The central cross member (3)
Like the left and right cross members (4) and (4) described above, the cross members are formed of an aluminum hollow extruded material having a hollow section penetrating in the extrusion direction (length direction) and having a substantially Japanese character cross section.

On the other hand, as shown in FIG. 3, the front cross member (2F) has a hollow portion (2F) penetrating in the extrusion direction (length direction).
It is formed from an aluminum hollow extruded material having a substantially cross-sectional shape having a). Inside the hollow part (2a) of this hollow extruded material, a reinforcing partition wall part (2b) formed integrally with the peripheral wall part
Are arranged so as to extend in the length direction. A joint (30) is fixedly connected to each of the left and right ends of the front cross member (2F) by welding. The connection structure of each joint (30) will be described later. The left and right joints (30) are connected to the above-mentioned left and right rear frames (8) via a bush (B) described later, as shown in FIG.

On the other hand, left and right side members (6) (6)
Is formed from an aluminum hollow extruded material having a substantially circular cross section and having a hollow portion penetrating in the extrusion direction (length direction).

Next, the connection structure between the left and right cross members (4) (4) and the joints (20) (20) in the rear cross member (2R) will be described. The connection structure between the left cross member (4) and the joint portion (20) and the connection structure between the right cross member (4) and the joint portion (20) are identical to each other. ) And the joint structure of the joint part (20) will be mainly described.

The joint (20) connected to the end of the left cross member (4), as shown in FIGS.
It is formed of an aluminum hollow extruded material having a bush mounting hole (22) formed of a hollow portion having a circular cross section penetrating in the extrusion direction, and includes a substantially cylindrical bracket (23). The bush mounting hole (22) is a portion that functions as a bush mounting portion (21) to which the floating bush (B) having a rubber elastic portion is mounted. In the bush mounting hole (22), the floating bush is provided. (B)
Are mounted by press fitting. Then, a flat mounting surface (2) is attached to a part of the outer peripheral surface of the bracket (23).
The mounting plate part (26) having 4) is integrally formed.
Further, a pair of positioning projections (25) (25) extending in the pushing direction are formed on both side edges of the mounting surface (24) so as to protrude substantially perpendicularly to the mounting surface (24) and are integrally formed. ing. The mounting surface (24) abuts on the end surface of the left cross member (4) in a substantially surface-contact state, and the side surfaces (25) of both protruding portions (25) and (25) oppose each other.
a) (25a) is in contact with the outer peripheral surface of the left cross member (4) so as to sandwich the left cross member (4). The end opening (4c) of the left cross member (4) is attached to the mounting surface (24).
Almost completely obstructed. Then, in this state, the mounting surface portion (24) and the protruding portion (25) are attached to the end surface and the outer peripheral surface of the left cross member (4) by welding such as MIG welding or laser beam welding. The entire peripheral wall portion is joined (W is a welded portion), and the joint portion (20) is fixedly connected to the end of the left cross member (4) by this joining. Similarly, a joint (20) is connected to an end of the right cross member (4).

On the other hand, the front cross member (2F) and the joint (3
0) are connected as follows. That is, FIG.
As shown in (a) and (b), the front cross member (2F)
The joint (30) connected to the end of the joint (20)
Similarly to the above, it is formed of an aluminum hollow extruded material having a bush mounting hole (32) formed of a hollow portion having a circular cross section penetrating in the extrusion direction, and comprises a bracket (33) having a substantially triangular cross section. The bush mounting hole (32) is a portion that functions as a bush mounting portion (31) to which the floating bush (B) having a rubber elastic portion is mounted. In the bush mounting hole (32), the floating bush is provided. (B) is mounted by press fitting. (37) is a hole penetrated in the extrusion direction for weight reduction. Then, on a part of the outer peripheral surface of the bracket (33),
A mounting plate (36) having a flat mounting surface (34) is integrally formed. Further, a positioning projection (35) extending in the extrusion direction is formed integrally with the edge of the mounting surface (34) so as to project substantially perpendicularly to the mounting surface (34). Then, the mounting surface portion (34) comes into contact with the end surface of the front cross member (2F) in a substantially surface contact state,
The side surface (35a) of the positioning projection (35) is in contact with the outer peripheral surface of the front cross member (2F). The end opening (2c) of the front cross member (2F) is almost completely closed by the mounting surface (34). And in this state,
The mounting surface portion (34) and the protruding portion (35) are formed on the end surface and the outer peripheral surface of the front cross member (2F) over the entire circumference of the peripheral wall portion of the front cross member (2F) by welding such as MIG welding or laser beam welding. The joints (30) are fixedly connected to the ends of the front cross member (2F) by joining.

In the sub-frame (1) having the above-described structure, when connecting the left and right cross members (4) of the rear cross member (2R) and the joint portion (20), the mounting surface of the joint portion (20) is used. Since the positioning projections (25) and (25) are formed on both side edges of 24), the joint (2
0) is connected to the end of the cross member (4), the side surface (25a) of the positioning projection (25) is brought into contact with the outer peripheral surface of the cross member (4), whereby the joint portion (2) is connected.
Positioning 0) can be easily performed. Similarly, when connecting the front cross member (2F) and the joint (30), the mounting surface (3) of the joint (30) is also used.
Since the positioning projection (35) is formed at the edge of (4), the positioning of the joint (30) can be easily performed. Therefore, according to the sub-frame (1), the connection work of the joints (20) and (30) can be easily performed, and the manufacturing cost of the sub-frame (1) can be reduced.

Furthermore, the end of the front cross member (2F)
Since the mounting surface (34) of the joint (30) is joined to the end surface of the front cross member (2F), not only the end but also the entire front cross member has high rigidity. have. Similarly, the ends of the left and right cross members (4) of the rear cross member (2R) are in a constrained state because the end surfaces thereof are joined to the mounting surface (24) of the joint (20). Therefore, the end portions of the left and right cross members (4) and the entire rear cross member have high rigidity similarly to the front cross member. Therefore, even when a load is applied to the joints (20) and (30), the ends of the cross members (2F), (4) and (4) are not unintentionally deformed.

Of course, these cross members (2F)
(4) In a state where the joints (20) and (30) are connected to the ends of (4), the joints (20) and (30) are connected to the bush as in the conventional example shown in FIG. The bracket (2) is not welded and fixed over most of the mounting part.
3) The mounting surface (2) formed on a part of the outer peripheral surface of (33)
4) Because the structure is welded and fixed at (34), the hole diameter of the bush mounting holes (22, 32) formed in the joints (20, 30) has almost changed. Therefore, the bush (B) can be smoothly mounted in the bush mounting holes (22) and (32).

Further, the front and rear cross members (2F) (3)
(4) (4) and the left and right side members (6) (6)
Since both are made of aluminum hollow extruded material, weight reduction is achieved, and these members (2F) (3)
(4) (4) (6) (6) can be manufactured efficiently. Moreover, in this embodiment, the joints (20) (30)
Since the joints (20) and (30) are also formed from a hollow extruded material, the joints (20) and (30) can be manufactured efficiently. For this reason, the manufacturing cost of the subframe (1) can be significantly reduced.

In addition, according to the subframe (1), the end opening (2c) of the cross member (2F) (4) (4)
Since (4c) is closed, it is possible to prevent intrusion of muddy water and the like in the puddle.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various settings can be changed.

For example, in the above embodiment, the side surfaces (25a) and (35a) of the positioning projections (25) and (35) are in contact with the outer peripheral surface of the cross member.
It may be in contact with the inner peripheral surface of the cross member.

In the above embodiment, the joint (20)
(30) is connected to the end of the cross member, but may be connected to the end of the side member in the present invention.

In the above embodiment, the number of cross members is two, and the number of side members is also two. However, in the invention of claim 1, the number of cross members is one. The number of side members may be three or more. The number of side members may be one or three or more.

[0046]

As described above, according to the present invention, since the mounting surface portion is joined to the end surface of the member, a hole into which a boss or the like is fitted is formed on the outer peripheral surface of the end portion of the member. Therefore, the manufacturing process of the subframe can be simplified, and the manufacturing cost of the subframe can be reduced.

Further, by joining the mounting surface to the end face of the member, the end of the member can be in a restrained state, so that the rigidity of not only the end of the member but also the entire member can be improved. . In addition, the rigidity of the end portion of the member can be improved without increasing the thickness of the end portion of the member, so that the weight of the subframe can be reduced. In addition, since the joint can be joined to the end of the member without directly joining most of the joint, a predetermined portion of the joint that may occur when the joint is joined ( The dimensional change of the bush mounting portion or the like can be prevented or suppressed.

When the sub-frame main body is formed by connecting a pair of front and rear cross members and a pair of left and right side members to each other in a substantially rectangular shape (claim 2), high strength is achieved. The vehicle sub-frame provided with the sub-frame main body of (1) can be provided.

The member to which the joint is connected is formed of a hollow extruded material having a hollow portion penetrating in the length direction, and the member has an end opening closed by a mounting surface. When the mounting surface is joined to the end face of the member (claim 3), the weight of the sub-frame can be reduced, and the member can be manufactured efficiently, so that the manufacturing cost of the sub-frame is increased. Can be further reduced. Further, since the end opening of the member is closed by the mounting surface, the rigidity of the end of the member can be further increased, and the intrusion of muddy water or the like into the water pool can be prevented.

When the joint portion is formed of a hollow extruded material having a bush mounting hole penetrating in the extrusion direction (claim 4), the joint portion can be manufactured efficiently, and The manufacturing cost of the frame can be further reduced.

Further, the cross member and the side member are
When connected to each other in a substantially orthogonal state (claim 5), it is possible to provide a vehicular sub-frame having a high-strength sub-frame main body.

When the cross member, the side member and the joint are all formed of a hollow extruded material (claim 6), the manufacturing cost of the sub-frame can be further reduced, and the weight is reduced. Sub-frames can be provided.

Also, a state in which the mounting surface of the joint abuts against the end surface of the member, and the side surface of the positioning protrusion formed on a part of the mounting surface abuts on the outer or inner peripheral surface of the member. When the joint is connected to the member, the joint can be easily positioned when the joint is connected to the end of the member. As a result,
The work of connecting the joint portion to the end of the member can be easily performed, so that the manufacturing cost of the subframe can be further reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a subframe according to an embodiment of the present invention.

FIGS. 2A and 2B are views showing a left cross member and a joint part in a rear cross member of the same sub-frame, wherein FIG. 2A is a perspective view showing the left cross member and the joint part separately, and FIG. It is a perspective view shown in the state after connecting with a joint part.

3A and 3B are views showing a front cross member and a joint portion of the sub-frame, wherein FIG. 3A is a perspective view showing the front cross member and the joint portion separately, and FIG. 3B is a diagram showing the front cross member and the joint portion. It is a perspective view shown in the state after connecting.

FIG. 4 is a plan view showing a structure of a rear portion of the vehicle body on which the subframe is installed.

FIG. 5 is a perspective view showing a structure of a rear portion of the vehicle body on which the subframe is installed.

FIG. 6A is a perspective view of a main part showing a conventional subframe, and FIG. 6B is a sectional view taken along line VI-VI in FIG.

[Explanation of symbols]

 1 Subframe 2F Front cross member 2R Rear cross member 4, 4 Left and right cross members in rear cross member 6, 6 Side member 20, 30 Joint part 22, 32 Bush mounting hole 24, 34 Mounting Surface part 25, 35: Positioning protrusion B: Floating bush

Continued on the front page. (72) Inventor Takeshi Nishiyama 1-7-2 Nishi Shinjuku, Shinjuku-ku, Tokyo Inside Fuji Heavy Industries Ltd. (72) Inventor Sadao Kokubo 1-480 Inuzuka, Oyama City, Tochigi Prefecture Showa Denko KK In-house (72) Inventor Masaharu Tochigi 1-480 Inuzuka, Oyama-shi, Tochigi Prefecture Showa Denko KK Oyama Office F-term (reference) 3D003 AA01 AA04 AA07 AA10 AA11 BB01 CA14 CA18 CA48 DA08

Claims (7)

[Claims] 1. One or more cross members (2F, 2R) extending in the left-right direction of the vehicle body and one or more side members (6, 6) extending in the front-rear direction of the vehicle body. Subframe body (10) formed by being connected to each other in a predetermined shape
And a joint part (20, 30) connected to an end of at least one of a cross member and a side member in the subframe body (10). The joint part (20, 30) is provided with the sub-frame main body (10).
It has an attachment surface part (24, 34) attached to the member, and that the joint part (20, 30) is connected by joining the attachment surface part (24, 34) to the end face of the member. Characteristic vehicle subframe. 2. The sub-frame main body (10) is formed by connecting a pair of front and rear cross members (2F, 2R) and a pair of left and right side members (6, 6) to each other in a substantially rectangular shape. The vehicle sub-frame according to claim 1, wherein 3. A member to which the joints (20, 30) are connected is formed of a hollow extruded material having hollow portions (2a, 4a) penetrating in the extrusion direction, and an end of the member. Openings (2c, 4c) are attached to the mounting surface (24, 3
The vehicle subframe according to claim 1 or 2, wherein the mounting surface (24, 34) is joined to an end surface of the member in a state where the member is closed by (4). 4. The joint according to claim 1, wherein said joint portion is formed of a hollow extruded material having a bush mounting hole penetrating in a pushing direction. Subframe for vehicles. 5. The vehicle sub-frame according to claim 1, wherein said cross member and said side member are connected to each other in a substantially orthogonal state. . 6. The cross member (2F, 2R), the side member (6, 6) and the joint portion (20, 30) are all formed of a hollow extruded material. The vehicle subframe according to claim 1. 7. A mounting surface portion (2) of the joint portion (20, 30).
4, 34) contact the end surface of the member, and the side surfaces (25a, 35a) of the positioning projections (25, 35) formed on a part of the mounting surface on the outer peripheral surface or the inner peripheral surface of the member. 2. The member is joined to the member in a state where the member is in contact with the member.
The vehicle subframe according to any one of claims 1 to 6.