The present disclosure relates to automobile undercarriage parts.
Background technology
[0002]
　Due to the stricter fuel economy regulations in recent years, the weight of automobile bodies is required to be reduced, and the weight of automobile undercarriage parts constituting the automobile bodies is also required to be reduced. However, simply replacing the material of the component with a material having high strength and a thin plate thickness may reduce the rigidity. Therefore, it is desirable to meet the demand for weight reduction by improving the component structure.
[0003]
　As a structure of an automobile suspension component, Patent Document 1 discloses a rear wheel suspension arm of an automobile. Patent Document 1 describes a structure in which a plate member covers an upper arm having an open cross-sectional shape, a structure in which partition wall members are provided at intervals along the bending direction of the upper arm, and a structure between a pair of vertical flanges of the upper arm. A structure provided with an intermediate vertical wall is disclosed. Patent Document 2 discloses a suspension arm in which recesses are formed in the arm main body at predetermined intervals along a bending direction.
Prior art literature
Patent documents
[0004]
Patent Document 1: Japanese Patent Application Laid-Open No. 8-27923
Patent Document 2: Japanese Patent Application Laid-Open No. 8-332820
Outline of the invention
Problems to be solved by the invention
[0005]
　For example, in the front lower arm as shown in FIG. 1, when a load in the direction from the front portion of the vehicle body to the rear portion of the vehicle body (direction D in FIG. 1) is input to the end portion 10a on the wheel mounting side, the end on the vehicle body mounting side is applied. From the portion 10b as a starting point, twisting deformation of the entire arm is likely to occur.
[0006]
　The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to suppress torsional deformation of automobile undercarriage parts.
Means to solve problems
[0007]
　One aspect of the present disclosure that solves the above problems is an automobile undercarriage component, which includes a groove-shaped arm member and a plate-shaped reinforcing member, and the arm member includes a top wall portion and a first. The ridgeline portion, the second ridgeline portion, the first side wall portion, and the second side wall portion are provided, and the top wall portion includes a first attachment portion at the first end portion, and the top wall portion is provided. The portion includes a second attachment portion at a second end portion, the first ridge line portion is sandwiched between the top wall portion and the first side wall portion, and the second ridge line portion is the heaven. It is sandwiched between the wall portion and the second side wall portion, the first ridge line portion and the second ridge line portion are along the extending direction of the top wall portion, and the reinforcing member is the bottom wall portion. A third ridge line portion and a flange portion are provided, the third ridge line portion is sandwiched between the bottom wall portion and the flange portion, and the bottom wall portion is the first side wall portion and the second side wall portion. The cross section of the automobile undercarriage component, which is joined to the side wall portion of the vehicle and includes the arm member and the reinforcing member, is a closed cross section, and the third ridge line portion is the first side wall portion and the second side wall portion. The flange portion is connected to the side wall portion of the above, the flange portion is joined to the top wall portion between the first mounting portion and the second mounting portion, and the flange portion is the first side wall portion and the first side wall portion. It is characterized in that it is connected to the side wall portion of 2.
The invention's effect
[0008]
　It is possible to suppress torsional deformation of automobile undercarriage parts.
A brief description of the drawing
[0009]
[Fig. 1] Fig. 1 is a diagram showing a shape example of an automobile undercarriage component.
[Fig. 2] Fig. 2 is a perspective view showing a schematic configuration of an automobile undercarriage component.
FIG. 3 is a perspective view of the automobile undercarriage component of FIG. 2 as viewed from the back.
[Fig. 4] It is a plan view of an automobile undercarriage part.
[Fig. 5] Fig. 5 is an exploded view of an automobile undercarriage component of FIG.
FIG. 6 is a diagram showing a cross section taken along the line AA in FIG. The AA cross section is a cross section of an automobile undercarriage component including an arm member and a reinforcing member.
FIG. 7 is a diagram showing a cross section taken along the line BB in FIG. The BB cross section is a cross section of an automobile undercarriage component including a flange portion of a reinforcing member.
FIG. 8 is a perspective view showing an example of a shape of a reinforcing member.
FIG. 9 is a schematic view showing a connection position of a third ridge line portion with respect to a first side wall portion and a second side wall portion.
FIG. 10 is a schematic view showing a connection position of a third ridge line portion with respect to a first side wall portion and a second side wall portion.
FIG. 11 is a diagram for explaining a preferable position of the first flange portion.
FIG. 12 is a diagram showing a shape example of a reinforcing member.
[FIG. 13] FIG. 13 is an exploded view of an automobile undercarriage component of FIG.
FIG. 14 is a diagram for explaining a preferable position of the second flange portion.
FIG. 15 is a diagram for explaining preferable positions of a first flange portion and a second flange portion.
FIG. 16 is a diagram showing the results of simulation (1).
FIG. 17 is a diagram showing the results of simulation (2).
FIG. 18 is a diagram showing the results of simulation (3).
FIG. 19 is a load-stroke diagram.
FIG. 20 is a diagram showing the results of simulation (4).
FIG. 21 is a diagram for explaining an analysis model of simulation (5).
FIG. 22 is a diagram showing the results of simulation (5).
FIG. 23 is a diagram for explaining an analysis model of simulation (6).
FIG. 24 is a diagram showing the results of simulation (6).
FIG. 25 is a diagram showing the results of simulation (7).
Embodiment for carrying out the invention
[0010]
　Hereinafter, one embodiment of the present disclosure will be described with reference to the drawings. In the present specification and the drawings, the elements having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.
[0011]
　The "automobile undercarriage parts" in the present specification are, for example, lower arms, upper arms and the like. In the present embodiment, the front lower arm is taken as an example of the automobile undercarriage component 1. As shown in FIGS. 2 to 5, the automobile undercarriage component 1 of the present embodiment is a component extending in three directions, and includes a groove-shaped arm member 10 and a plate-shaped reinforcing member 20. ..
[0012]
　The arm member 10 of the present embodiment includes a top wall portion 11, a first ridge line portion 12a, a second ridge line portion 12b, a first side wall portion 13a, and a second side wall portion 13b. .. In the arm member 10 of the present embodiment, the center line of the member connecting the first end portion 10a and the second end portion 10b is the first ridge line portion in a plan view viewed from a direction perpendicular to the top wall portion 11. It is a member curved with the 12a side inside. The top wall portion 11 has a first end portion 10a and a second end portion 10b. In the case of the present embodiment, the first end portion 10a is the end portion on the wheel mounting side, and the second end portion 10b is the end portion on the vehicle body mounting side.
[0013]
　The first end 10a of the arm member 10 includes a first mounting portion P 1 and a. The first mounting portion P 1 is a portion to which other parts are mounted, and the first mounting portion P 1 of the present embodiment has a hole 16 for mounting a wheel-side component (for example, a knuckle). There is. The first mounting portion P herein 1 is the center of the bore 16. The second end portion 10b of the arm member 10 includes a second attachment portion P 2 . The second mounting portion P 2 is a portion to which other parts are mounted, and the second mounting portion P 2 of the present embodiment has a hole 17 for mounting a component on the vehicle body side (for example, a front subframe). doing. The second attachment portion P 2 in the present specification is the center of the hole 17.
[0014]
　The first ridge line portion 12a of the arm member 10 is sandwiched between the top wall portion 11 and the first side wall portion 13a. The second ridge line portion 12b of the arm member 10 is sandwiched between the top wall portion 11 and the second side wall portion 13b. Such a first ridge line portion 12a and a second ridge line portion 12b extend along the extending direction of the top wall portion 11.
[0015]
　The first ridge line portion 12a of the present embodiment includes a first curved portion 14a curved inward of the top wall portion 11 and a first straight portion 15a. That is, the center of curvature of the first curved portion 14a is outside the top wall portion 11, and the top wall portion 11 does not exist between the center of curvature and the first curved portion 14a. The first straight portion 15a is located on the side of the first end portion 10a with respect to the first curved portion 14a. The second ridge line portion 12b of the present embodiment includes a second curved portion 14b curved to the outside of the top wall portion 11 and a second straight portion 15b. That is, the center of curvature of the second curved portion 14b is outside the top wall portion 11, and the top wall portion 11 is located between the center of curvature and the second curved portion 14b. The second straight portion 15b is located on the side of the first end portion 10a with respect to the second curved portion 14b. The arm member 10 of the present embodiment has a third end portion 10c that is branched from the second curved portion 14b and extends toward the outside of the top wall portion 11. The third end portion 10c of the present embodiment is an end portion on the vehicle body mounting side. The arm member 10 may not have the first curved portion 14a and the second curved portion 14b, and the arm member 10 may be linear as a whole. Further, the arm member 10 does not have to have the third end portion 10c.
[0016]
　The reinforcing member 20 has a bottom wall portion 21, a third ridgeline portion 22, and a flange portion 23. The bottom wall portion 21 of the reinforcing member 20 is joined to each of the first side wall portion 13a of the arm member 10 and the second side wall portion 13b of the arm member 10. Therefore, the opening of the groove-shaped arm member 10 is partially covered by the bottom wall portion 21 of the reinforcing member 20. That is, the automobile undercarriage component 1 has a portion where the cross section perpendicular to the longitudinal direction of the component is a closed cross section as shown in FIG. 6 due to the bottom wall portion 21 of the arm member 10 and the reinforcing member 20.
[0017]
　As shown in FIGS. 3 and 5, the third ridge line portion 22 of the reinforcing member 20 is sandwiched between the bottom wall portion 21 and the flange portion 23. The third ridge line portion 22 is located between the first side wall portion 13a and the second side wall portion 13b, and is connected to the first side wall portion 13a and the second side wall portion 13b. In addition, the "connection" between parts in the present specification includes a form in which the parts are simply in contact with each other and a form in which the parts are joined by welding, for example. When the bottom wall portion 21 and the side wall portions 13a and 13b are joined, the joining method is not particularly limited, and for example, arc welding may be adopted. When the bottom wall portion 21 and the side wall portions 13a and 13b are arc-welded, it does not have to be full-circle welding.
[0018]
　The flange portion 23 is connected to the bottom wall portion 21 via a third ridge line portion 22. Flange portion 23 extends toward the top wall portion 11 of the arm member 10, the first mounting portion P of the arm member 10 1 and the second mounting portion P of the arm member 10 2 top wall 11 between It is joined to. Therefore, at the position where the flange portion 23 of the reinforcing member 20 is provided, the inner space of the closed cross section formed by the arm member 10 and the reinforcing member 20 is covered with the flange portion 23 as shown in FIG. ing. The method of joining the flange portion 23 of the reinforcing member 20 and the top wall portion 11 of the arm member 10 is not particularly limited, and for example, arc welding may be adopted. When the flange portion 23 of the reinforcing member 20 and the top wall portion 11 of the arm member 10 are arc-welded, it does not have to be full-circle welding.
[0019]
　The flange portion 23 is connected to the first side wall portion 13a of the arm member 10 and the second side wall portion 13b of the arm member 10. From the viewpoint of further improving the effect of suppressing the torsional deformation of the automobile undercarriage component 1, it is preferable that the flange portion 23 is joined to the first side wall portion 13a and the second side wall portion 13b.
[0020]
　The automobile undercarriage component 1 of the present embodiment is configured as described above. The automobile undercarriage component 1 of the present embodiment is directed toward the first end portion 10a, which is the end portion on the wheel mounting side when the vehicle is running, for example, from the front portion of the vehicle body to the rear portion of the vehicle body (in the present embodiment, in FIG. 4). The load is input in the direction D). At this time, since the second end portion 10b and the third end 10c is an end portion of the vehicle body mounting side in a state of being restrained, the first mounting portion P of the arm member 10 1 , the torsional deformation A triggering moment is generated. On the other hand, in the automobile suspension component 1 of the present embodiment, the length of the arm member 10 is apparently shortened due to the provision of the reinforcing member 20 provided with the flange portion 23. This length corresponds to LL 1 ( difference between the length L and the length L 1 ) in FIG. 11 described later . As a result, torsional deformation can be suppressed.
[0021]
　By suppressing the torsional deformation as described above, the deformation strength as a component can be improved. Moreover, since the component structure is not complicated, it also contributes to weight reduction. Therefore, in the automobile undercarriage component 1 of the present embodiment, the bottom wall portion 21 of the reinforcing member 20 and the arm member 10 form a partially closed cross section, and the flange portion 23 of the reinforcing member 20 forms the apparent arm member 10. Due to the synergistic effect of shortening the length, it is possible to secure the deformation strength and reduce the weight at the same time.
[0022]
　When the arm member 10 has the first curved portion 14a, when a load is applied to the first end portion 10a in the direction from the front portion of the vehicle body to the rear portion of the vehicle body (direction D in FIG. 4 in this embodiment), the first Stress is concentrated on the top wall portion 11 and the first side wall portion 13a in the curved portion 14a of 1. Therefore, in the top wall portion 11 passing through the first curved portion 14a, out-of-plane deformation such as bending in the direction perpendicular to the top wall portion 11 (vehicle height direction) is likely to occur. However, in the automobile suspension component 1 provided with the reinforcing member 20, a closed cross section is formed in the first curved portion 14a by the arm member 10 and the reinforcing member 20. As a result, the bending rigidity of the top wall portion 11 and the first side wall portion 13a in the first curved portion 14a is improved, and out-of-plane deformation is less likely to occur. That is, when the reinforcing member 20 as in the present embodiment is provided on the arm member 10 having the first curved portion 14a, it is possible to obtain the effect of suppressing the out-of-plane deformation in addition to the effect of suppressing the torsional deformation. can.
[0023]
　In the example of FIG. 6, the bottom wall portion 21 is connected to the tips of the first side wall portion 13a and the second side wall portion 13b. On the other hand, in order to easily join the bottom wall portion 21 to the first side wall portion 13a and the second side wall portion 13b, the third ridge line portion 22 is the arm member 10 as shown in FIGS. 8 to 9. It is preferable to stand with respect to the first side wall portion 13a and the second side wall portion 13b. FIG. 9 is a schematic view showing the connection position of the third ridge line portion 22 with respect to the first side wall portion 13a and the second side wall portion 13b. In the present specification, the term "standing" of the third ridge line portion 22 with respect to the first side wall portion 13a and the second side wall portion 13b means, for example, in the cross section of the automobile undercarriage component 1 as shown in FIG. , A state in which the third ridge line portion 22 is not located at the tip portions of the first side wall portion 13a and the second side wall portion 13b. For example, in the case of the connection position of FIG. 10, since the third ridge line portion 22 is located at the tip of the first side wall portion 13a and the second side wall portion 13b, the first side wall portion 13a and the first side wall portion 13a and the second side wall portion 13b are located. It cannot be said that it stands with respect to the side wall portion 13b of 2.
[0024]
　As shown in FIG. 9, when the third ridge line portion 22 stands with respect to the first side wall portion 13a and the second side wall portion 13b, the bottom wall portion 21, the first side wall portion 13a, and the first side wall portion 13a. For example, fillet welding can be performed on the side wall portion 13b of 2. This facilitates the manufacture of the automobile undercarriage component 1 and improves productivity.
[0025]
　The flange portion 23 is preferably located between the first straight portion 15a and the second straight portion 15b of the arm member 10. In the cross section of the component 1 passing through the flange portion 23, it is desirable that the flange portion 23 is in contact with the first side wall portion 13a, the second side wall portion 13b, and the top wall portion 11. Then, the flange portion 23 can resist the cross-sectional deformation due to the torsional deformation of the component 1. More preferably, the flange portion 23, the first side wall portion 13a, the second side wall portion 13b, and the top wall portion 11 are joined to each other. Further, it is desirable that the side of the flange portion 23 in contact with the first side wall portion 13a, the second side wall portion 13b and the top wall portion 11 is longer. That is, the flange portion 23 closes the entire cross section of the component 1, and the entire length of the side of the flange portion 23 in contact with the arm member 10 is joined to the arm member 10. In order to resist the torsional deformation of the component 1. Most desirable.
[0026]
　When the arm member 10 has the first curved portion 14a, the position of the flange portion 23 of the reinforcing member 20 is preferably close to the load input point. More specifically, the position of the flange portion 23 is preferably in the following range. As shown in FIG. 11, first, a curve is defined in which the outer line of the first ridge line portion 12a is fitted by curvature in a plan view viewed from a direction perpendicular to the top wall portion 11. This curve is referred to as the first curve C F. Next, the centroid of the cross section of the part (front lower arm in this embodiment) cut along the normal extending in the radial direction R from the center of curvature O of the first curve C F is calculated. Then, a curve passing through the center of gravity of each cross section is defined. This curve is referred to as a second curve C. Next, on the second curve C, the length from the second mounting portion P 2 of the second end portion 10b to the first mounting portion P 1 of the first end portion 10a (hereinafter, “mounting portion”). The interval length ") is defined as L. Further, on the second curve C, the second mounting portion P of the second end 10b 2 from length to the flange portion 23 of reinforcing member 20 (hereinafter, "first length") L Defined as 1 . When the length L between the mounting portions and the first length L 1 are defined as described above, the first length L 1 is preferably 83% or more of the length L between the mounting portions. As a result, torsional deformation can be effectively suppressed, and the mass efficiency of deformation strength can be further improved. The first length L The upper limit of 1 is appropriately changed according to the shape of the arm member 10 and the shape of the mating part in consideration of the mounting space of the parts, etc., but the first length L 1 is, for example, the length L between the mounting portions. It is 95% or less.
[0027]
　Assuming that the flange portion 23 is referred to as a first flange portion 23a, the reinforcing member 20 may have a second flange portion 23b as shown in FIGS. 12 and 13 as another flange portion 23. good. The second flange portion 23b is provided between the first flange portion 23a and the second mounting portion P 2 of the arm member 10 . The second flange portion 23b extends toward the top wall portion 11 of the arm member 10 and is joined to the top wall portion 11. Further, the second flange portion 23b is connected to the first side wall portion 13a and the second side wall portion 13b of the arm member 10. When the second flange portion 23b is provided in addition to the first flange portion 23a, the bending rigidity of the arm member 10 can be further increased, and the deformation strength can be improved.
[0028]
　Here, as shown in Figure 14, on the second curve C, the second mounting portion P of the second end portion 10b 2 length from to the second flange portion 23b (hereinafter, "second The length of ") is defined as L 2 . At this time, the second length L 2 is preferably 36% or less of the length L between the mounting portions. Thereby, the mass efficiency of the deformation strength can be effectively improved. From the viewpoint of improving the mass efficiency of the deformation strength, the second length L 2 is more preferably 30% or less of the length L between the mounting portions. The second length L 2 lower limit is appropriately changed according to the shape of the shape and mating part of the arm member 10 in consideration of the installation space of components such as the second length L 2 is For example, it is 10% or more of the length L between the mounting portions.
[0029]
　In the above description, the length L between the attachment portions, the first length L 1 and the second length L 2 are defined based on the first curve C F and the second curve C. These lengths may be defined based on the line C'shown in FIG. The line C'is an outline of the first ridge line portion 12a so as to pass through the first mounting portion P 1 and the second mounting portion P 2 in a plan view viewed from a direction perpendicular to the top wall portion 11. It is an offset line. Under this definition, between the attachment portion length L is on the line C ', the second mounting portion P 2 from the portion P first attachment 1 is the length of up to. Further, the first length L 1 is the length from the second mounting portion P 2 to the first flange portion 23 a on the line C' . Further, the second length L 2 is the length from the second mounting portion P 2 to the second flange portion 23 b on the line C' .
[0030]
　A mounting portion based on the length L between the mounting portions based on the second curve C of FIGS. 11 and 14, the first length L 1 and the second length L 2, and the mounting portion based on the line C'of FIG. Strictly speaking, the lengths of the interval length L, the first length L 1 and the second length L 2 are different. However, when considering the ratios such as L 1 / L and L 2 / L, the length L between the mounting portions, the first length L 1 and the second length L 2 are the second curve C and the line. The preferred numerical range of L 1 / L and L 2 / L remains substantially unchanged regardless of which line of C'is defined . That is, even when the length L between the mounting portions, the first length L 1 and the second length L 2 are defined based on the line C' , the first length L 1 is the length between the mounting portions. It is preferably 83% or more of the L. Further, the second length L 2 is preferably 36% or less of the length L between the mounting portions.
[0031]
　Although the embodiment according to the present disclosure has been described above, the present disclosure is not limited to such an example. It is clear that a person skilled in the art can come up with various modifications or amendments within the scope of the technical ideas described in the claims, and of course, these are also the technical scopes of the present disclosure. It is understood that it belongs to.
Example
[0032]

　Deformation simulation was performed using the analysis model of the front lower arm. The analysis model has the same structure as that of FIGS. 3 and 4, and is a model having a first flange portion 23a. In the simulation, with the second end portion 10b and the third end portion 10c constrained, the first end portion 10a is stroked along the direction from the front portion of the vehicle body to the rear portion of the vehicle body (direction D in FIG. 4). It is carried out under the conditions. In addition, as a comparative example, an analysis model without a flange was created and a simulation was performed under the same conditions. The result of simulation (1) is shown in FIG. The model with the “flange portion” in FIG. 16 is the same as the model 1 in the simulation (4) described later.
[0033]
　As shown in FIG. 16, in the analysis model having the first flange portion, the load can be increased with respect to the stroke amount of the first end portion, and the deformation strength can be improved as compared with the comparative example. can.
[0034]
A
　similar simulation was performed with an analysis model in which the position of the first flange portion was different. Further, the same simulation was carried out in the analysis model having the first flange portion and the second flange portion in which the positions of the first flange portions are different. When the second flange portion is provided (second length L 2 / length between mounting portions L) is 0.29. As Reference Example 1, the same simulation was carried out using an analysis model in which the entire groove-shaped arm member was covered with a plate to form a closed cross-sectional structure. In the analysis model of Reference Example 1, neither the first flange portion nor the second flange portion is provided. The result of simulation (2) is shown in FIG. The vertical axis of FIG. 17 is standardized by the simulation result of Reference Example 1, and the value indicated by the vertical axis is the mass efficiency of the deformation strength of each analysis model obtained by the simulation. It is a dimensionless value obtained by dividing by the mass efficiency of the intensity.
[0035]
　As shown in FIG. 17, the larger (first length L 1 / length L between attachment portions), the higher the mass efficiency of the deformation strength. In particular, in this simulation result, the mass efficiency of the deformation strength is improved as compared with Reference Example 1 when L 1 / L is 0.83 or more. Therefore, from the viewpoint of effectively improving the mass efficiency of the deformation strength, the first length L 1 is more preferably 83% or more of the length L between the mounting portions.
[0036]
In
　a structure provided with a first flange portion and a second flange portion, a similar simulation was performed with an analysis model in which the positions of the second flange portions are different. (First length L 1 / length L between attachment portions) is 0.95. The result of simulation (3) is shown in FIG. The vertical axis of FIG. 18 is standardized by the simulation result of Reference Example 1, and the value indicated by the vertical axis is the mass efficiency of the deformation strength of each analysis model obtained by the simulation. It is a dimensionless value obtained by dividing by the mass efficiency of the intensity.
[0037]
　As shown in FIG. 18, in this simulation result, the mass efficiency was the highest when (second length L 2 / length between attachment portions L) was 0.29. In particular, in this simulation result, the mass efficiency of the deformation strength is improved as compared with Reference Example 1 when L 2 / L is 0.36 or less. Therefore, from the viewpoint of effectively improving the mass efficiency of the deformation strength, the second length L 2 is more preferably 36% or less of the length L between the mounting portions.
[0038]

　Simulation was performed using a plurality of analysis models in which the welding positions of the flanges with respect to the arm members are different from each other. The shapes of the arm member and the reinforcing member are the same as those shown in FIGS. 3 to 6, and the flange portion is the wall of the top wall portion of the arm member, the first side wall portion, and the second side wall portion. It is in contact with the club. The welding position of the flange portion with respect to the arm member in each model is as follows.
　　Model 1: Top wall part, first side wall part, second side wall part
　　Model 2: Top wall part only
　　Model 3: First side wall part, second side wall part
　　Model 4: Non-joined
[0039]
　In this simulation, the rigidity is evaluated by moving the first end portion 10a along the direction D in FIG. 4 as in the simulation (1). Rigidity is evaluated by the slope of a straight line in a region where the stroke and the load are proportional to each other in the load-stroke diagram (eg, FIG. 19). It can be said that the larger the slope of this straight line, the higher the rigidity. The result of simulation (4) is shown in FIG. As shown in FIG. 20, the model 1 and the model 2 in which the flange portion of the reinforcing member is joined to the top wall portion of the arm member have high rigidity with respect to other models. From this, it can be seen that if the top plate portion and the flange portion are joined, the joining to the side wall portion does not contribute much to the rigidity.
[0040]
A simulation was performed with a plurality of analysis models in which
　the welding lengths L w (FIG. 21) of the flange portion 23 and the top wall portion 11 were changed with respect to the model 1 of the simulation (4) . The result of simulation (5) is shown in FIG. The arm width W in FIG. 22 is the distance between the first side wall portion 13a and the second side wall portion 13b of the arm member 10. As shown in FIG. 22, even a model in which the entire region of the flange portion 23 is not joined to the top wall portion 11 has high rigidity.
[0041]

　with respect to model 2 Simulation (4), the width W of the flange portion 23 F and the simulation of a plurality of the analytical model (Fig. 23) is changed. In this simulation, the width W F of the flange portion 23 and the above-mentioned welding length L w are equal to each other. The result of simulation (6) is shown in FIG. As shown in FIG. 24, the model in which the flange portion 23 is connected to the first side wall portion 13a and the second side wall portion 13b has high rigidity, but when the width W F is short, the rigidity is high. It has dropped significantly. Therefore, it is preferable that the flange portion 23 is connected to the first side wall portion 13a and the second side wall portion 13b.
[0042]

　An analysis model in which the third ridge line portion 22 of the reinforcing member 20 stands on the first side wall portion 13a and the second side wall portion 13b as shown in FIGS. 8 and 9 (hereinafter referred to as “” The simulation was carried out with model 5 ”). The flange portion of the model 5 is joined to each wall portion of the top wall portion 11 of the arm member, the first side wall portion 13a, and the second side wall portion 13b. The result of simulation (7) is shown in FIG. The model to be compared with the model 5 is the model 1 of the simulation (4). Model 1 is a model of FIG. 10 in which the third ridge line portion 22 does not stand with respect to the first side wall portion 13a and the second side wall portion 13b. The only difference between the model 1 and the model 5 is whether or not the third ridge line portion 22 stands with respect to the first side wall portion 13a and the second side wall portion 13b. As the result of FIG. 25 shows, the model 5 has a higher rigidity than the model 1 which has the highest rigidity in the above-mentioned simulations (4) to (6). Therefore, from the viewpoint of improving the rigidity, it is preferable that the third ridgeline portion of the reinforcing member stands with respect to the first side wall portion and the second side wall portion of the arm member.
Industrial applicability
[0043]
　The technique according to the present disclosure can be used, for example, as a front lower arm of an automobile.
Code description
[0044]
1 Automotive undercarriage parts
10 Arm member
10a First end
10b Second end
10c Third end
11 Top wall
12a First ridge
12b Second ridge
13a First side wall
13b First 2 Side wall portion
14a First curved portion
14b Second curved portion
15a First straight portion
15b Second straight portion
16 Hole
17 Hole
20 Reinforcing member
21 Bottom wall portion
22 Third ridgeline portion
23 Flange portion
23a First Flange portion
23b 2nd flange portion
C F 　　　1st curve
C 2nd curve
C'A line
L P 2 offset from the outline of the 1st ridge line portion Length from P 1 to P 1
L 1 Length from 　　　P 2 to the first flange
L 2 Length from 　　　P 2 to the second flange
L w 　　　Welding length between the flange and the top wall
O 1st Center of curvature of curve
P 1 　　　First mounting part
P 2 　　　Second mounting part
R Radial direction
W Arm width
W F 　　　Flange width
The scope of the claims
[Claim 1]
　It is an automobile undercarriage component and includes a
　groove-shaped arm member and a plate-shaped reinforcing member, and the
　arm member includes a top wall portion, a first ridge line portion, a second ridge line portion, and a second. The
　top wall portion is provided with a side wall portion of 1 and a second side wall portion, the top wall portion is provided with a first attachment portion at a first end portion, and the
　top wall portion is provided with a second attachment portion at a second end portion. includes a mounting portion,
　the first ridge line portion is sandwiched between the first side wall portion and the top wall portion,
　the second ridge portion is interposed between the second side wall portion and the top wall ,
　the second ridge portion and the first ridge portion is not along the extending direction of the top wall,
　the reinforcing member has a bottom wall, and a third ridge portion, and a flange portion provided,
　said third ridge portion is sandwiched between the flange portion and the bottom wall portion,
　the bottom wall, joined to said second side wall portion and the first side wall portion,
　the said arm member The cross section of the automobile undercarriage component including the reinforcing member is a closed cross section,
　the third ridge line portion is connected to the first side wall portion and the second side wall portion, and the
　flange portion is An
　automobile undercarriage component that is joined to the top wall portion between the first mounting portion and the second mounting portion, and the flange portion is connected to the first side wall portion and the second side wall portion. ..
[Claim 2]
　The automobile suspension component according to claim 1, wherein the third ridgeline portion stands on the first side wall portion and the second side wall portion.
[Claim 3]
　The automobile undercarriage component according to claim 1 or 2, wherein the flange portion is joined to the first side wall portion and the second side wall portion.
[Claim 4]
　The first ridge line portion includes a first curved portion curved inside the top wall portion, and
　the first ridge line portion is first on the side of the first end portion from the first curved portion. It includes a straight portion,
　the second ridge portion, a second curved portion curved to the outside of the top wall,
　the second ridge portion, the first from the second curved portion
　Claims 1 to 3 include a second straight portion on the end side, and the cross section of the automobile undercarriage component including the flange portion includes the first straight portion and the second straight portion. Any of the car undercarriage parts.
[Claim 5]
　The automobile undercarriage component according to claim 4, wherein the first length L 1 is 83% or more of the length L between the mounting portions.
　First length L 1 : The length from the second mounting portion to the flange portion
　on the wire C'Length between the mounting portions L: The second mounting portion on the wire C'. Length
　line to the mounting portion of 1 C': The first ridge line so as to pass through the first mounting portion and the second mounting portion in a plan view seen from a direction perpendicular to the top wall portion. A line that offsets the outline of the part
[Claim 6]
　The reinforcing member includes a first flange portion and a second flange portion as the flange portion, and
　the first length L 1 is described from the second mounting portion on the line C'. The automobile undercarriage component according to claim 5, which is the length to the first flange portion, and
　the second length L 2 is 36% or less of the length L between the mounting portions.
　Second length L 2 : The length from the second mounting portion to the second flange portion on the line C'.