KR100315723B1 - Suspension arm of sheet metal make - Google Patents

Abstract

In the sheet metal suspension arm composed of the arm body 1 and the reinforcing member connected to the arm body 1 while forming a box-shaped cross section, the production cost can be reduced by increasing the material utilization rate. Since the reinforcing member is divided into a plurality of reinforcing pieces (2, 3; 4 to 6), the blank layout of the reinforcing pieces (2, 3) can be made at the remaining portion between the blank layout portions for the arm body (1). . The arm body 1 is shaped so that its cross section is close to the C shape, and the reinforcing pieces 2 and 3 are shaped to be close to the plate shape. In the case of the L-shaped suspension arm, for easy fabrication of the blank layout of the reinforcing pieces 2, 3, each of the reinforcing pieces 2, 3 is tapered while going toward each end of the suspension arm.

Description

Suspension arm made of sheet metal {SUSPENSION ARM OF SHEET METAL MAKE}

TECHNICAL FIELD The present invention relates to a suspension arm used for a strut type front suspension of a motor vehicle or the like.

Forged suspension arms are generally used as such suspension arms, but sheet metal suspension arms are also used to reduce the weight of the suspension arms.

In such sheet metal suspension arms, rigidity can be secured by having the arm body and a reinforcing member joined thereto to have a box-shaped cross section. Until now, this reinforcing member is made of a single press-molded material similarly to the arm body.

Such a conventional reinforcing member is to be large. Therefore, it is difficult to make the blank layout (stock layout) of the arm body and the reinforcing member with a high material utilization rate from a single coil strip, resulting in a large material cost.

In this case, it is conceivable to make the blank layout of the arm body and the reinforcing member from separate coil strips in order to increase the material utilization rate. In this case, however, a separate press-forming apparatus for press working the arm body and the reinforcing member separately is required, and as a result, cost reduction cannot be expected.

The object of the present invention in view of the above problems of the prior art is to provide a suspension arm that can be manufactured at low cost.

1 is a plan view of one embodiment of the present invention.

2 (A), 2 (B) and 2 (C) are lines A-A of FIG. Sectional view taken along B-B and C-C.

3 is a plan view of a blank layout of an arm body and a reinforcing piece given as a first embodiment of the present invention.

4 is a plan view of a second embodiment of the present invention;

Fig. 5 is a plan view of a blank layout of an arm body and a reinforcing piece given as a second embodiment of the present invention.

6 is a plan view of a third embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

1: Arm main body 2, 3, 4-6: reinforcement piece

In order to achieve the above object, the present invention provides a sheet metal suspension arm comprising an arm body and a reinforcing member coupled to the arm body so as to have a box-shaped cross section, wherein the reinforcing member is composed of a plurality of reinforcing pieces. The reinforcing pieces are characterized in that they are respectively joined to the arm body by welding.

According to this configuration of the present invention, it is possible to reduce the size of each reinforcing member, thereby distributing a plurality of reinforcing members in the remaining portion of the coil strip remaining between the blank layout portions for the arm body, thereby making the material higher. The utilization allows for the blank layout of the reinforcement. In this way, a cheap suspension arm can be obtained by reducing the material cost.

In order to further reduce the cost of the suspension arm, it is preferable to use a so-called cutting and sequential press working method having a low processing cost. However, in such cutting and sequential press processing, the product is not punched out of the coil strip until the product is molded into the final shape. Therefore, when molding by press working, accurate molding is difficult due to the influence of the blank layout portion for the arm body and the blank layout portion for the reinforcing piece. In such a case, when the arm main body is made to have a C-shaped cross section or when the reinforcing piece is made into a shape close to the flat plate, molding of the reinforcing piece becomes easy. In this way, the blank layout portion for the arm body and the blank layout portion for the reinforcement piece are less affected by each other. As a result, even if the gap between the blank layout portion for the arm body and the blank layout portion for the reinforcement piece is reduced to increase the material utilization rate, the arm body and the reinforcement piece can be cut and sequentially transferred to presses while maintaining a high material utilization rate. Can be. Therefore, the cost of the suspension arm can be further reduced.

In the strut-type front suspension, the load in the vertical direction (up-down direction) is absorbed by the damper, and the load in the longitudinal direction (front-rear direction) is absorbed by the suspension arm. Therefore, the following configuration is adopted. That is, the suspension arm is made so that the shape on the top view is close to the L-shape. At one end of the suspension arm is provided a wheel side connection. The other end and the bent part of the suspension arm are respectively provided with a vehicle body side connection part. When the arm portion between the bent portion and the other end faces in the longitudinal direction, the vehicle body side connecting portion at the bent portion and the other end is pivotally supported by the vehicle body with a longitudinal span. In this way, the supporting rigidity in the longitudinal direction can be secured. When this kind of suspension arm is composed of a sheet metal arm composed of a reinforcing member joined to the arm main body so that the cross-sectional shape on the top view becomes an L-shaped arm main body and a box-shaped cross section, the reinforcing member is the arm main body. It can be divided into two or more reinforcing pieces extending toward each end of the arm body from the bent portion of. In this way, as in the example described above, an inexpensive suspension arm can be obtained by reducing the material cost.

The bending stress generated in the L-shaped suspension arm is greatest at the bent portion of the suspension arm, and the bending stress is not so great at each end of the suspension arm. Therefore, even if the portion of the reinforcing piece close to each end of the arm body becomes smaller than the width of the arm body, there is no problem in terms of strength. By narrowing the tip of the reinforcing piece, it is possible to make the layout of the reinforcing piece with high material utilization in the remaining portion between the blank layout portions for the arm body. In this way, it is possible to further increase the use of materials while further reducing costs.

1 shows a suspension arm used for strut front suspension of a motor vehicle. As shown in the drawing, the suspension arm is composed of an arm main body 1 close to the L-shape and a reinforcing member coupled to the arm main body 1. The reinforcing member includes a reinforcing piece 2 extending from the vicinity of the bent portion of the arm body 1 toward one end of the arm body 1 and a reinforcing piece 3 extending from the bent portion to the other end of the arm body 1. It consists of.

At one end of the arm main body 1, a joint mounting hole 1a, which is a wheel side connection portion, is formed, and a ball joint is installed in the joint mounting hole, and is connected to the lower end of a knuckle supporting the rotation of the wheel. do. In addition, a bush 1b fitted with rubber serving as a vehicle body side connection portion is attached to the bent portion of the arm body 1, which is rotatably supported by the vehicle body with a bolt (not shown). Moreover, at the other end of the arm body 1, a pin 1c serving as a vehicle body side connection portion is attached, which pin is rotatably supported by the vehicle body by a bush (not shown). In this way, the suspension arm is pivotally supported by the vehicle body with the bush 1b and the pin 1c aligned on the same longitudinal line.

As shown in Fig. 2 (A), 2 (B) and (2C), the cross section of the arm main body 1 has a shape close to the C shape. On the other hand, the reinforcement pieces 2 and 3 are a form close to a flat plate. When each of the reinforcing pieces 2 and 3 is joined to the arm body 1 by arc welding or the like, a box-shaped cross section is obtained.

The reinforcing piece 2 has a shape close to a tapered triangle going toward one end of the arm main body 1, and the inner side 2a of the reinforcing piece 2 in the curvature inner side of the arm main body 1 is the arm main body. The outer side 2b which adjoins along the inner diameter edge of (1) and which is in a curvature outer side part is inclined with respect to the outer radius edge of the arm main body 1. As shown in FIG. In this way, the inner side 2a is connected with the inner diameter edge of the arm main body 1, and the outer side 2b is connected with the convex part 1d of the width direction center formed in the arm main body 1. . With this configuration, the bending stiffness in the vicinity of the end of the suspension arm is reduced. However, since the bending stress generated at the end of the suspension arm is not so great, there is no problem in terms of strength.

The reinforcing piece 3 is provided as follows, that is, the inner side 3a of the reinforcing piece 3 in the curvature inner part of the arm main body 1 adjoins along the inner diameter edge of the arm main body 1, and has curvature. The outer side edge 3b in the outer side part follows the outer diameter edge of the arm main body 1 from the bending part to the intermediate point between this bend part and the other end of the arm main body 1. Between the other end of the arm body 1 and the intermediate point, the outer side 3b deviates inward from the outer diameter edge of the arm body 1, and thus, near the other end of the arm body in the reinforcing piece 3. The part has a width smaller than the width of the arm body 1. In this way, the inner side 3a is connected to the inner diameter edge of the arm main body 1, and the outer side 3b is not only with the pin 1c at the other end of the arm main body 1, but also of the arm main body at the bend. It is also connected to the outer diameter edge. With this configuration, the bending stiffness in the vicinity of the other end of the suspension arm is reduced, but there is no problem in terms of strength, because the bending stress that occurs at the other end of the suspension arm is not so large, and also the bending portion where a large bending stress is generated This is because is reinforced with the reinforcing piece 3 over the whole area.

If it is not necessary to consider the strength at the time of attaching the pin 1c, the outer side 3b is moved away from the outer diameter edge of the arm body 1 near the bent portion, and the reinforcing piece 3 is shown in Fig. 1. It can also be shaped like a triangle.

The blank layout (stock layout) of the arm main body 1 and the reinforcement pieces 2 and 3 is made of the common coil strip 10 as shown in FIG. These are simultaneously formed by press working in parallel with cutting and sequential feeding. In this press forming method, unlike when each reinforcing member is made from one wide plate member, the reinforcing piece 2, 3 is carried out to the remaining portion between the blank layouts remaining after removing the arm body 1 portion from the plate material. ), Blank layout can be used to increase the material utilization. In addition, since the reinforcing pieces 2 and 3 are molded close to the flat plate shape, the forming of the reinforcing pieces 2 and 3 becomes easy. Even if the spacing between the reinforcing pieces 2 and 3 and the arm body 1 becomes smaller as well as the spacing between the reinforcing pieces 2 and 3, mutual effects such as elongation (tension) of the material as a result of the press work will be observed. The arm main body 1 and the individual reinforcement pieces 2 and 3 can be press-processed with high accuracy by this. Therefore, it is possible to minimize the cost of the suspension arm by minimizing the material cost.

In the illustrated embodiment, for the two right and left suspension arms, the blank layout shows that the arm body 1 and the reinforcing pieces 2, 3 are separated from the common coil strip 10 in two right and left symmetrical sets. You can get it.

In the figure, reference numeral 11 denotes a pilot hole for positioning during cutting and sequential transfer of the coil strip 10. This pilot hole 11 is formed in the blank layout part for the arm main body 1, and the blank layout part for the reinforcement pieces 2 and 3, respectively. The pilot hole 11 can also be used for positioning when the arm main body 1 and the reinforcing pieces 2 and 3 are joined to each other.

In the first embodiment, the reinforcing portion for reinforcing the bent portion of the arm body 1 is formed of one of the reinforcing pieces 2, 3 (for example, the reinforcing piece 3). However, as shown in FIG. 4, the reinforcement part can be divided into the reinforcement pieces 2 and 3 by dividing the reinforcement part in the center part of the bend part. By such a configuration, even if the interval between the blank layout portions for the arm body 1 becomes smaller than that of the above-described embodiment, as shown in Fig. 5, the blank layout of the reinforcing pieces 2 and 3 within such intervals is shown. And as a result, the material utilization rate can be further increased. In this embodiment, the cross-sectional shape of each part of the suspension arm is as shown in Figures 2 (A), 2 (B) and 2 (C).

In the embodiment of FIGS. 1 and 4, the reinforcing member is divided into two reinforcing pieces 2, 3. However, the number of divisions is not limited to two. In other words, as shown in FIG. 6, the reinforcing member may be divided into three parts, that is, the reinforcing piece 4 connected to the bent portion of the arm body 1 and the arm at one end of the arm body 1. The reinforcing piece 5 connected with an arm part, and the reinforcing piece 6 connected with the arm part in the other end of the arm main body 1 are comprised. However, when the reinforcing member is divided into four or more parts, it takes a long time to connect these parts. Therefore, it is preferable to make the number of reinforcement pieces into two to three pieces.

As mentioned above, although the suspension arm used for the strut-type front suspension was demonstrated, this invention can be applied also to other forms of suspension.

According to the present invention as described above, it is possible to reduce the size of each reinforcing member, accordingly, by dispersing a plurality of reinforcing members in the remaining portion of the coil strip remaining between the blank layout portion for the arm body, a higher material The utilization allows for the blank layout of the reinforcement. In this way, a cheap suspension arm can be obtained by reducing the material cost. In addition, by narrowing the tip of the reinforcing piece, the layout of the reinforcing piece can be made within the remaining portion between the blank layout portions for the arm body, with high material utilization.

Claims (3)

An arm main body 1 and a reinforcing member coupled to the arm main body 1 so as to have a box-shaped cross section, the reinforcing member substantially extending over the entire length of the arm main body 1, and the arm main body 1 In a sheet metal suspension arm in which the layout of the reinforcing member) and the reinforcing member are made from a common coil strip 10, The reinforcement member is divided into a plurality of reinforcement pieces 2 and 3 when the blank layout is made from a common coil strip 10, and these reinforcement pieces 2, 3 and 4 to 6 have a gap between the reinforcement pieces. A sheet metal suspension arm, which is joined to the arm body (1) by welding in a state where the single circumferences meet each other so as not to occur. The suspension arm according to claim 1, wherein the arm main body (1) has a cross section close to the C-shape, and the reinforcing pieces (2, 3; 4 to 6) have a shape close to a flat plate. The shape in the plan view is close to the L-shape, the arm main body 1 having a wheel-side connection at one end, and the car body-side connection at the other end and the bend, respectively, and a reinforcement coupled to the arm body so as to have a box-shaped cross section. A reinforcing member which extends substantially over the entire length of the arm body (1), wherein the layout of the arm body (1) and the reinforcing member is made from a common coil strip (10). , When making a blank layout in the common coil strip 10, the reinforcing member is provided with at least two reinforcing pieces 2, 3; 4 extending from the bend of the arm body 1 toward each end of the arm body 1. To 6), These reinforcing pieces 2, 3; 4 to 6 are respectively joined to the arm body 1 by welding in a state where the stepped edges abut each other so that a gap does not occur between the reinforcing pieces, The site | part near each end of the arm main body 1 in the site | part of the said reinforcement piece 2, 3; 4-6 is the arm main body corresponding to the said site | part of each reinforcement piece 2, 3; 4-6. The sheet metal suspension arm, which is narrowed with a width smaller than the width of the portion of (1).