1. The automobile front lower control arm is characterized by comprising a first main body part (1) and a second main body part (2), wherein the first main body part (1) and the second main body part (2) are both pipe-shaped parts, the first main body part (1) comprises a first connecting end used for connecting a ball pin and a second connecting end provided with a first bushing (3),

the first main body part (1) is of a flat bent structure, the first main body part (1) sequentially comprises a first surface, a second surface, a third surface and a fourth surface along the circumferential direction, the first surface is opposite to the third surface, the second surface is opposite to the fourth surface, the widths of the first surface and the third surface are larger than the widths of the second surface and the fourth surface, the second surface is located on the outer side of the bent structure, and the fourth surface is located on the inner side of the bent structure;

the outer end of the second main body part (2) is provided with a second lining (4), the inner end of the second main body part (2) is welded with the middle connecting section (106) of the first main body part (1), and the inner end of the second main body part (2) is connected to the second surface of the first main body part (1).

2. The lower front control arm for a vehicle of claim 1, further comprising: the first connecting end of the first main body part (1) is provided with a ball pin connecting area (107), pipe walls corresponding to a first surface and a second surface in the ball pin connecting area (107) are attached to each other, hollow protruding structures (108) are arranged on two sides of the first connecting end, the hollow protruding structures (108) wrap the edge of the ball pin connecting area (107), and connecting holes penetrating through the first surface and the second surface are formed in the connecting area.

3. The lower front control arm for a vehicle of claim 2, wherein: the first connecting end comprises a first section (101) and a second section (102) from outside to inside;

the first surface of the first segment (101) is of a convex structure, the second surface of the first segment (101) is of a concave structure, the first surface and the second surface of the second segment (102) are of a concave structure, and the connecting area of the second segment (102) is gradually reduced from outside to inside.

4. The lower front control arm for a vehicle of claim 1, further comprising: a third section (103) is arranged between the first connecting end of the first main body part (1) and the middle connecting section (106), and the third section (103) is of a square tube structure.

5. The lower front control arm for a vehicle of claim 1, further comprising: the first surface and the second surface of the middle connecting section (106) of the first main body part (1) are respectively provided with corresponding waist-shaped grooves (109), and the length direction of each waist-shaped groove (109) is arranged along the length direction of the first main body part (1).

6. The lower front control arm for a vehicle of claim 1, further comprising: a strip-shaped groove (110) is formed in the first surface between the middle connecting section (106) of the first main body portion (1) and the second connecting end, and the strip-shaped groove (110) is formed in the length direction of the first main body portion (1).

7. The lower front control arm for a vehicle of claim 6, further comprising: a fourth segment (104) and a fifth segment (105) are sequentially arranged between the middle connecting section (106) and the second connecting end of the first main body part (1), the fourth segment (104) is adjacent to the middle connecting section (106), and the strip-shaped groove (110) extends from the fourth segment (104) to the fifth segment (105);

a side groove face (111) is arranged between the first surface and the second surface of the fourth segment (104), and the side groove face (111) is crescent-shaped.

8. The lower front control arm for a vehicle of claim 1, further comprising: the second connecting end of the first main body part (1) is provided with an arc-shaped groove penetrating through the first surface and the second surface, and the first bushing (3) is welded in the arc-shaped groove.

9. The lower front control arm for a vehicle of claim 1, further comprising: the size of the inner end of the second main body part (2) along the length direction of the first main body part (1) is larger than the size along the thickness direction of the first main body part (1).

10. The lower front control arm for a vehicle according to any one of claims 1 to 9, wherein: the difference in circumference between the first body portion (1) and the respective segments is less than 10%.

Background

Control arm, also known as swing arm, is automobile suspension's important component part before the car, and control arm is in the same place wheel and automobile body elastic ground connection through ball pivot or bush respectively down before the car, and its effect is:

1. the wheel hub and the vehicle body are connected, and the wheel hub and other components are used for restraining and guiding the wheel, so that the wheel has proper parameters in the running process, the running stability is ensured, and the eccentric wear of the tire is reduced.

2. Together with springs, dampers, etc., to receive and transmit the weight of the vehicle body.

3. The longitudinal force of vehicle acceleration and braking and the transverse force during steering are borne.

Conventional control arms are generally solid members, and for example, patent application No. CN208558920U discloses a front control arm of a front suspension of an automobile, which is a solid structure with an M-shaped or i-shaped cross section. Along with the design requirement of light weight of the vehicle, the control arm buckled by punching is widely applied. For example, patent application No. CN206589593U discloses a front lower control arm, which is formed by fastening and welding upper and lower half stamping parts, but this method can reduce the weight to some extent, but the fastening and overlapping part is long, the length of the weld joint is long, the welding deformation is large, and the overall material utilization rate is low, which can only reach about 65%.

Disclosure of Invention

The invention aims to provide an automobile front lower control arm, which can effectively reduce the length of a welding seam and improve the utilization rate of materials.

The invention discloses an automobile front lower control arm, which comprises a first main body part and a second main body part, wherein the first main body part and the second main body part are both pipe-shaped parts, the first main body part comprises a first connecting end used for connecting a ball pin and a second connecting end provided with a first bushing,

the first main body part is of a flat bent structure and sequentially comprises a first surface, a second surface, a third surface and a fourth surface along the circumferential direction, the first surface is opposite to the third surface, the second surface is opposite to the fourth surface, the widths of the first surface and the third surface are both larger than the widths of the second surface and the fourth surface, the second surface is positioned on the outer side of the bent structure, and the fourth surface is positioned on the inner side of the bent structure;

the outer end of the second main body part is provided with a second bushing, the inner end of the second main body part is welded with the middle connecting section of the first main body part, and the inner end of the second main body part is connected to the second surface of the first main body part.

Preferably, the first connection end of the first main body part is provided with a ball pin connection area, pipe walls corresponding to the first surface and the second surface in the ball pin connection area are attached to each other, two sides of the first connection end are hollow protruding structures, the hollow protruding structures wrap around the edge of the ball pin connection area, and the connection area is internally provided with a connection hole penetrating through the first surface and the second surface.

Preferably, the first connecting end comprises a first section and a second section from outside to inside;

the first surface of the first section is of a convex structure, the second surface of the first section is of a concave structure, the first surface and the second surface of the second section are of concave structures, and the connecting area of the second section is gradually reduced from outside to inside.

Preferably, a third section is arranged between the first connecting end and the middle connecting section of the first main body part, and the third section is of a square tube structure.

Preferably, the first surface and the second surface of the middle connecting section of the first main body part are respectively provided with corresponding waist-shaped grooves.

Preferably, a strip-shaped groove is formed in a first surface between the middle connecting section of the first main body part and the second connecting end, the strip-shaped groove is formed in the length direction of the first main body part, and the length direction of the waist-shaped groove is formed in the length direction of the first main body part.

Preferably, a fourth section and a fifth section are sequentially arranged between the middle connecting section and the second connecting end of the first main body part, the fourth section is adjacent to the middle connecting section, and the strip-shaped groove extends from the fourth section to the fifth section;

a side groove surface is disposed between the first surface and the second surface of the fourth segment, the side groove surface being crescent-shaped.

Preferably, the second connecting end of the first body portion has an arc-shaped groove penetrating the first and second surfaces, and the first bushing is welded in the arc-shaped groove.

Preferably, the inner end of the second main body portion has a dimension in the length direction of the first main body portion greater than a dimension in the thickness direction of the first main body portion.

Preferably, the difference in circumference between the first body portion and each segment is less than 10%.

The invention has the beneficial effects that: the utility model provides a first main part of lower control arm and second main part all adopt the pipe forming part before the car, and the main part only has the welding point between first main part and the second main part, compares in upper and lower two halves stamping workpiece lock welded control arm, can reduce welding seam length 70% under the prerequisite of proof strength, effectively reduce part weight and volume, promote material utilization 20%, reduce welding deformation, promote the product size qualification rate, reduce cost.

Drawings

FIG. 1 is a front view of the present invention;

FIG. 2 is a cross-sectional view A-A of FIG. 1;

FIG. 3 is a cross-sectional view B-B of FIG. 1;

FIG. 4 is a cross-sectional view of C-C of FIG. 1;

FIG. 5 is a cross-sectional view D-D of FIG. 1;

FIG. 6 is a cross-sectional view E-E of FIG. 1;

FIG. 7 is a cross-sectional view F-F of FIG. 1;

FIG. 8 is a cross-sectional view G-G of FIG. 1;

FIG. 9 is a cross-sectional view H-H of FIG. 1;

FIG. 10 is a top view of the present invention;

FIG. 11 is a left side view of the present invention;

fig. 12-23 are stress analysis diagrams of the front lower control arm under 12 working conditions of vertical jump, braking, starting, reversing, right steering, left steering, forward passing threshold, reversing passing threshold, vertical impact, longitudinal impact, left wheel lateral impact and right wheel lateral impact in sequence.

Fig. 24 is a graph showing a reduction ratio analysis of the first main body portion.

Reference numerals: the first body part 1, the first segment 101, the second segment 102, the third segment 103, the fourth segment 104, the fifth segment 105, the middle connecting segment 106, the ball and pin connecting region 107, the hollow convex structure 108, the kidney-shaped groove 109, the strip-shaped groove 110, the side groove surface 111, the second body part 2, the first liner 3, and the second liner 4.

Detailed Description

The present invention is further described below.

As shown in fig. 1, 10 and 11, the lower front control arm of an automobile disclosed by the invention comprises a first main body part 1 and a second main body part 2, wherein the first main body part 1 and the second main body part 2 are both pipe-shaped parts, and the first main body part 1 comprises a first connecting end for connecting a ball pin and a second connecting end provided with a first bushing 3;

the first main body part 1 is of a flat bent structure, the first main body part 1 sequentially comprises a first surface, a second surface, a third surface and a fourth surface along the circumferential direction, the first surface is opposite to the third surface, the second surface is opposite to the fourth surface, the widths of the first surface and the third surface are both larger than the widths of the second surface and the fourth surface, the second surface is positioned on the outer side of the bent structure, and the fourth surface is positioned on the inner side of the bent structure;

the outer end of the second main body part 2 is provided with a second bushing 4, the inner end of the second main body part 2 is welded with the middle connecting section 106 of the first main body part 1, and the inner end of the second main body part 2 is connected to the second surface of the first main body part 1.

The first main body part 1 is a curved pipe molding, as shown in fig. 1, the front side of the paper surface in the drawing is a first surface, the back side of the paper surface is a third surface, the right side is a second surface, and the left side is a fourth surface. The integral installation hard point of the front lower control arm is basically consistent with that of the existing front lower control arm, and correct assembly of a vehicle and front wheel positioning parameters are guaranteed. The first body part 1 is entirely bent toward the fourth surface, and the second body part 2 is connected to the second surface, that is, the bent second body part 2 is connected to the outside of the bent point. Overall, in addition to the welding between the main body portion and the bush, there is only a circumferential weld between the first main body portion 1 and the second main body portion 2, so the length of the weld can be greatly reduced.

The front lower control arm in the buckling form of the existing two half stamping parts can be respectively provided with structures such as reinforcing ribs and the like and then buckled and welded, but a pipe forming part is difficult to weld a reinforcing structure, so that the strength of the pipe forming part can be ensured to meet the requirement only through the change of the sectional shape of the pipe forming part, and the first main body part 1 and the second main body part 2 are respectively formed by processing a pipe fitting, so that the material distribution of each section of the first main body part 1 and the second main body part 2 is basically the same, the same as the solid structure or the two half buckling structures in the background art cannot be realized, and the size and the material consumption of the section can be adjusted according to the stress of the section. In actual design and processing, the maximum thinning rate is required to be less than the elongation rate of the material, and for better forming and processing, the difference of the perimeter lengths of the first main body part 1 and each segment is less than 10 percent. For this reason, the present application designs the respective segments of the lower front control arm as follows.

As shown in fig. 2 and 3, in a preferred embodiment of the present application, a ball pin connection area 107 is disposed at the first connection end of the first body portion 1, pipe walls corresponding to a first surface and a second surface in the ball pin connection area 107 are attached to each other, hollow protrusion structures 108 are disposed at two sides of the first connection end, the hollow protrusion structures 108 are wrapped around the edge of the ball pin connection area 107, and a connection hole penetrating through the first surface and the second surface is disposed in the ball pin connection area 107. The corresponding pipe walls of the ball pin connecting area 107 are attached to each other, so that the bolt torque can be ensured to completely act on the ball pin, and the torsion attenuation caused by overcoming the gap when the bolt is tightened can be avoided. The hollow convex structures 108 on the two sides of the first connecting end are wrapped at the edge of the ball pin connecting area 107, so that on one hand, the situation that the two sides exceed the extension rate of materials to cause cracking can be avoided, and on the other hand, the hollow convex structures 108 are wrapped at the edge of the ball pin connecting area 107 to provide higher structural strength and stress performance of the first connecting end for the ball pin connecting area 107.

On this basis, as shown in fig. 2 and 3, the first connecting end includes, from outside to inside, a first segment 101 and a second segment 102; the first surface of the first segment 101 is a convex structure, the second surface of the first segment 101 is a concave structure, the first surface and the second surface of the second segment 102 are both concave structures, and the connection region of the second segment 102 is gradually reduced from the outside to the inside. As shown in fig. 1, since the first segment 101 is generally provided with two connection holes along the width direction, and only the middle of the second segment 102 is provided with one connection hole, for the convenience of installation, the hollow convex structures 108 on both sides of the first segment 101 are processed on one side of the second surface, so that the first surface forms a convex structure, the second surface forms a concave structure, and the connection area of the second segment 102 is gradually reduced from outside to inside and gradually transits to a square tube structure, in order to reduce the deformation rate of the material, so as to facilitate the forming and achieve a good effect, both the first surface and the second surface of the second segment 102 are concave structures, so that both sides of the tube wall of the second segment 102 can share part of the deformation respectively.

As shown in fig. 4, a third segment 103 is disposed between the first connection end and the middle connection segment 106 of the first main body 1, and in order to ensure the stress performance, the third segment 103 is a square tube structure. Compared with the conventional round tube structure, the square tube structure has stronger bending resistance.

As shown in fig. 1 and 5, the middle connecting section 106 of the first main body part 1 is a section connecting the first main body part 1 and the second main body part 2, and is a stress concentration area, in order to better distribute and transmit the stress therein, the first surface and the second surface are respectively provided with corresponding waist-shaped grooves 109, and the length direction of the waist-shaped grooves 109 is arranged along the length direction of the first main body part 1. Note that the kidney-shaped groove 109 is not a through-hole structure, but a closed groove structure formed by a pipe wall. The groove bottoms of the kidney-shaped grooves 109 of the first surface and the second surface are close to each other as much as possible, but the pipe walls cannot contact each other, and a certain gap needs to be maintained to prevent friction. During design and processing, care must be taken that the waist-shaped groove 109 cannot be torn or the stress performance of the waist-shaped groove 109 is affected. As shown in fig. 5, although the first surface and the second surface are provided with the symmetrical kidney-shaped grooves 109, the groove bottom of the kidney-shaped groove 109 and the second surface (i.e. the outer side of the curve) of the third segment 103 are still the places where the thinning rate of the whole first main body portion 1 is the greatest, and the whole thinning rate can be ensured to meet the requirement as long as the thinning rates at two places are ensured to meet the requirement.

As shown in fig. 1, the middle connection section 106 of the first main body portion 1 has a longer length from the second connection end, and is a substantially straight section, and in order to prevent the middle connection section 106 of the first main body portion 1 from deforming, a strip-shaped groove 110 is disposed on a first surface between the middle connection section 106 and the second connection end of the first main body portion 1, and the strip-shaped groove 110 is disposed along the length direction of the first main body portion 1. Generally, the strip-shaped grooves 110 only need to be disposed on the first surface, and the depth of the strip-shaped grooves 110 is much shallower than that of the kidney-shaped grooves 109, which can replace the reinforcing ribs to achieve the reinforcing effect.

As shown in fig. 6 and 7, a fourth segment 104 and a fifth segment 105 are sequentially arranged between the middle connecting section 106 and the second connecting end of the first body part 1, the fourth segment 104 is adjacent to the middle connecting section 106, the middle connecting section 106 of the first body part 1 is connected with the second body part 2, so that the connection between the two is the place where the stress is most concentrated, and since the second body part 2 is normally arranged in a direction deviated from the fourth segment 104, the fourth segment 104 also brings about a large stress, in this application, besides the strip-shaped groove 110 is extended from the fourth segment 104 to the fifth segment 105, a side groove surface 111 is arranged between the first surface and the second surface of the fourth segment 104, and the side groove surface 111 is in a crescent shape. The crescent-shaped side recessed surfaces 111 can well resist the outward stress of the second body 2, and prevent the deformation problem.

In order to ensure the connection of the first main body 1 and the first bushing 3, the second connection end of the first main body 1 has an arc-shaped groove penetrating the first surface and the second surface, and the first bushing 3 is welded in the arc-shaped groove. The second connection end is typically of a relatively wide dimension, which ensures the formation of an arcuate groove and the widthwise stress, since in general the width of the second connection end and the fifth segment 105 adjacent thereto is larger than the third segment 103.

The above description mainly refers to the construction of the first body part 1 and the following description refers to the construction of the second body part 2. As shown in fig. 1, 8 and 9, the length of the second main body 2 is much shorter, and it is mainly necessary to ensure the strength of the connection between the inner end and the outer end, especially the connection strength of the inner end, which is the place where the stress of the whole control arm is most concentrated, for this reason, in the preferred embodiment of the present application, the size of the inner end of the second main body 2 along the length direction of the first main body 1 is larger than the size along the thickness direction of the first main body 1. Thereby, the length of the welding seam between the first main body part 1 and the second main body part 2 can be increased in reply, the stability of the connection is ensured, and the bending resistance and the torsion resistance are satisfied. And the other end adopts a structure similar to the second connecting end of the first main body part 1, so that the connecting strength of the second main body part and the second lining 4 is ensured.

After the design processing with reference to the embodiment shown in fig. 1, the reduction rate is analyzed, as shown in fig. 24, in this embodiment, the maximum reduction rate is 15%, and the elongation rate of the selected material is 22% to meet the molding requirement. As shown in fig. 12 to 23, experiments were performed on vertical jump, braking, starting, reversing, right steering, left steering, forward passing threshold, reverse passing threshold, vertical impact, longitudinal impact, left wheel lateral impact, and right wheel lateral impact, respectively, and the results showed that the maximum stress was 340MPa, which was less than the yield limit of the selected material, and satisfied the design requirements.