KR101185357B1 - One-piece type low arm with improved reinforcement structure and the method of manufacturing the same - Google Patents

Abstract

The present invention relates to a low arm with improved reinforcing structure and a method of manufacturing the same, forming an outer shape of a low arm, and having an end protruding along an outer edge thereof, and having a groove formed in the inner side of the low arm and the lower arm base. It has a shape that can be added to the inner groove closely, and is mutually close fit by a spring back of the reinforcing end provided to face the protruding end of the low arm base portion, and is fixed to the low arm base portion Consisting of a reinforcement part, the vehicle weight can be reduced by reducing the weight of the roam itself, and the driving safety of the vehicle can be improved by securing the durability of the roam.

Description

ONE-PIECE TYPE LOW ARM WITH IMPROVED REINFORCEMENT STRUCTURE AND THE METHOD OF MANUFACTURING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace arm having an improved reinforcement structure using a spring back, and a method of manufacturing the same. In the single-plate furnace arm using high tensile steel sheet, an effective method for structurally reinforcing a portion where load is concentrated, The reinforcing piece is attached to the weak part, and the reinforcing piece is joined to each other by using a tight fit method utilizing the spring back phenomenon of the high tensile steel sheet, thereby improving the durability of the low arm as well as the weight. The present invention relates to a technology that can reduce vehicle weight through reduction.

In general, the suspension of the vehicle plays an important role in driving safety and steering of the vehicle, and while supporting the vehicle body stably from the wheel, and exhibits a function to suppress and attenuate road vibration transmitted from the wheel, Above all, securing structural safety comes first.

The suspension device of the vehicle connects the vehicle body and the wheel, and absorbs the shock from the road surface, a shock absorber for adjusting the operation of the spring, an arm and various links for controlling the operation of the wheel, and the like. It consists of.

In particular, a low arm, which is one of the main parts of the suspension of a vehicle, connects the crossbeam and the knuckle arm, and has a bow shape, and the frequency of breakage in a localized area where load is concentrated. Belongs to a relatively high part.

Through the improvement of the effective reinforcing structure of the loam, it is intended to reduce the weight of the parts by improving the running stability of the vehicle as well as to reduce the weight of the vehicle.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low arm having an improved reinforcement structure by using a springback which can effectively secure a structural rigidity for securing durability while reducing vehicle weight by reducing the weight of the component itself.

Another object of the present invention, in the manufacture of the single-plate low-arm, the low-arm having an improved reinforcement structure by using a spring back, excluding the welding method that can increase the local failure frequency during welding of the reinforcement To provide a method for producing a.

According to the idea of the present invention, a low arm has an outer shape, is provided with an end protruding along the outer edge, and has a groove in which a lower arm base is formed; And a shape in which the loam base portion is in close contact with the inner groove and is capable of being added thereto, and is mutually close fit by a spring back of a reinforcement end provided to face the protruding end of the loam base portion. It provides a low arm with an improved reinforcement structure using a spring back including a;

At this time, the low arm base portion and the low arm reinforcement is preferably made of a high tensile steel sheet material.

Here, the low arm base portion is made of a high-strength steel sheet, but is formed after the restrike processing (forming), it is preferable that the spring back does not occur at the protruding end.

In contrast, the low-arm reinforcement portion is made of a high-tensile steel sheet, but is not processed after the restrike processing, the springback is generated at the reinforcement end.

The low arm base part may have a tensile strength of 540 to 820 MPa, and the low arm reinforcement part may have a tensile strength of 600 to 900 MPa.

In addition, it is preferable that the low arm base part has a thickness of 2.0 to 4.0 mm, and the low arm reinforcement part has a thickness of 1.2 to 2.0 times the thickness of the low arm base part.

On the other hand, the low arm reinforcement portion is fixed to at least one or more of the weak structural rigidity of the low arm base portion, can reinforce the local structural strength on the low arm base portion, the low arm base portion to which the low arm reinforcement is coupled The structurally weak spot may be an arc center portion of the entire area of the ro-arm base portion having an arc-shaped link shape.

At this time, as a preferred embodiment, further comprising a fastening portion which is fastened through the ro-arm base portion and the ro-arm reinforcement at the same time to further strengthen the coupling between the ro-arm base portion and the ro-arm reinforcement to be mutually interference fit and fixed coalescing; can do.

Here, the fastening portion, the roam reinforcing portion is in close contact with at least two on the inner groove of the roam base formed by the addition is good, such as fastening, fastening bolts or fastening rivets may be used.

In addition, according to another aspect of the present invention, (a) forming a low arm base portion using a high tensile steel sheet; (b) subjecting the molded low arm base portion to a restrike process; (c) forming a low arm reinforcing part in a form corresponding to the size and shape of the structurally weak part of the low arm base part using a high tensile steel sheet; And (d) inserting and fixing the roam reinforcement to the structurally fragile portion of the roam base, and using the springback induced by the roam reinforcement to close fit the roam base and the roam reinforcement. It provides a method for producing a low arm having an improved reinforcement structure using a spring back comprising a.

In this case, in the step (c), the molded low arm reinforcement may not perform a separate list-like machining to induce the occurrence of springback.

In the step (d), the springback is not induced at the outer edge protruding end portion of the roam base portion subjected to the re-strike processing, and the springback is induced at the reinforcement end portion of the low-arm reinforcement portion which is not subjected to the re-listening processing, thereby forcing a mutual fit. It is preferable that the fixed coalescing is made.

In addition, after the step (d), (e) performing an additional fastening operation for strengthening the coupling between the low arm base portion and the low arm reinforcement to be mutually interfitted; may further include.

In the fastening operation in the step (e), it is preferable to perform bolt fixing or rivet fixing on the combined region of the low arm base part and the low arm reinforcing part.

According to the furnace arm having an improved reinforcement structure using the spring back of the present invention and a method for manufacturing the same, the reinforcing piece for securing structural rigidity is bonded to a local part where load concentration is induced in the structure of the furnace arm. Using the spring back phenomenon of the high tensile steel sheet, the reinforcing pieces are mutually bonded to each other on the structurally weak areas of the low arm by a tight fit, and then additional fastening means (e.g. bolts or rivets) are partially connected. In this case, it is possible to prevent an increase in breakage during welding of the existing reinforcing pieces in advance, and furthermore, there is a technical effect of securing more improved component durability.

In addition, according to the roam having an improved reinforcement structure using the spring back of the present invention and a method of manufacturing the same, optimal design of the roam structure in the form of a single plate using a high-tensile steel sheet as the material of the reinforcing piece to be combined with the roam as well as the roam. As a result, the effect of reducing the weight of the component can be realized, and furthermore, there is a technical effect that can reduce the weight of the vehicle.

1 is a view schematically showing a part of the box-shaped arm;
2 is a view for showing the internal structure of the box-shaped low arm shown in FIG.
Figure 3 is a view showing for explaining the general form of the single-plate loam,
4 is a view schematically showing a single plate-shaped loam according to an embodiment of the present invention;
FIG. 5 is a view illustrating a state in which a single plate-shaped low arm according to an embodiment of the present invention is tightly fitted by tightly fitting a low arm reinforcing part to a low arm base part using a spring back of a high tensile steel sheet; FIG. ,
FIG. 6 is a flowchart illustrating a method of manufacturing a single plate loam according to an embodiment of the present invention. FIG.

Hereinafter, a preferred embodiment of a single plate type loam having an improved reinforcement structure and a manufacturing method thereof using the spring back according to the present invention will be described.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings.

 The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Prior to describing the present invention, a brief description will be given of the structure of a general roam.

1 is a view schematically showing a part of the box-shaped low arm, and FIG. 2 is a view showing an internal structure of the box-shaped low arm shown in FIG. 1.

Referring to FIG. 1, the illustrated box-shaped arm has a shape that is joined by welding at both ends thereof to form a box-shaped hollow 15 therein by using two steel plates 10 and 20 divided into upper and lower parts. .

The internal structure of the box-shaped low arm can be confirmed through FIG. 2, and as shown in FIG. 2, both sides or one side of the two steel sheets 10 and 20 have a specific shape of reinforcement 12 and 14 to secure structural rigidity. ), You can see how the joint is inserted. The illustrated reinforcement (12, 14) is composed of two, but such a reinforcement (12, 14) is also shown in the form of the number is increased according to the type of the roam and the type of installation vehicle.

As described above, in the case of a box-shaped arm that has been commonly used, an increase in the weight of the product cannot be avoided because the joint is completed by welding using a plurality of members, and structural weakness of the weld site is a problem that impairs product durability. Also worked.

3 is a view showing a general shape of the single plate loam.

Referring to FIG. 3, the illustrated single plate loam 100 may solve the problem of the box type loam as described above with reference to FIGS. 1 and 2, that is, an increase in product weight, which could not but be increased by using multiple members. , Since it is manufactured in the form of a single plate when forming the low arm without additional welding, it has a form that can solve the problem that the product durability is impaired.

In the case of such a single plate type low arm 100, a high tensile strength steel sheet is mainly used, and as the weight of the product is reduced even though the thickness thereof is increased, it may be manufactured in a form suitable for a recent light weight trend of a vehicle.

However, even if such a single plate-type low arm 100 is manufactured by using a high tensile strength steel sheet, when the vehicle becomes larger and more heavy, the thickness of the single plate-type low arm 100 is increased to secure structural strength. Inevitably, additional configuration of the reinforcement is required as an effective solution.

However, when the reinforcement is joined to the end plate-shaped low arm 100 by using a conventional general welding method, the frequency of breakage may occur most severely in the welded reinforcement joint region, and thus an effective fixing method of welding objection is used. It is to be possible to incorporate the reinforcement into the furnace arm.

Figure 4 is a schematic diagram illustrating a single plate-shaped loam having an improved reinforcement structure using a springback according to an embodiment of the present invention.

4 clearly shows only the main feature parts in order to conceptually clearly understand the present invention, and as a result, various modifications of the drawings are expected, and the scope of the present invention need not be limited by the specific shapes shown in the drawings. none.

Referring to FIG. 4, the illustrated single plate low arm 100 forms the outline of the low arm, and has end portions 112a and 112b protruding along the outer edge thereof, and the groove 114 is formed on the inside thereof. It comprises a low arm base portion 110, and a low arm reinforcement portion 120 is fixedly incorporated into the low arm base portion 110 for the purpose of reinforcing the structural rigidity of the low arm base portion 110.

First, the low arm base unit 110 will be described.

The low arm base 110 refers to a pure single plate type loam to which the separate reinforcement means described above with reference to FIG. 3 is not applied.

However, in the present invention, for the improved reinforcement structure, since the roam reinforcement part 120 to be described later is fixedly named as a single plate type roam, the existing single plate type roam without the roam reinforcement part 120 is referred to as a roam base. The part 110 will be referred to as a name.

The low arm base 110 may be made of a high-strength steel sheet, and may include protruding end portions 112a and 112b protruding to a predetermined length along an outer edge thereof. And a groove is formed inward of these protruding ends 112a and 112b.

Since the shape and size of the low arm base 110 may be variously modified according to the size, shape, etc. of the vehicle to which the present invention is to be applied, the scope of the present invention is limited due to the specific shape of the low arm base 110 shown in FIG. There is no need to be limited or limited.

As the material of the low arm base 110, a high tensile strength steel sheet may be used, and after being molded into a target shape and size, it is subjected to a restrike processing.

Here, the wrist-like processing is a process that is performed to prevent a spring back phenomenon that may be caused after molding on a part molded using a high tensile steel sheet, and prevents springback after forming a part of a high tensile steel sheet. By increasing the dimensional accuracy, the assemblability with other parts can be improved.

However, in the case of the present invention, in the case of the low arm base portion 110 is subjected to a list-like process, the springback generation at the protruding end (112a, 112b) is blocked, but in the case of the low arm reinforcement portion 120 to be described later By not performing a re-like post-molding process, it takes a form that intentionally causes springback occurrence at the reinforcing ends 122a and 122b facing the protruding ends 112a and 112b. As a result, the protruding ends 112a and 112b and the reinforcing ends 122a and 122b are mutually close fit.

Detailed description related to this will be given later in the description of the roam reinforcement part 120.

The low arm base portion 110 is made of a high tensile steel sheet having a tensile strength of 540 to 820 MPa.

If the tensile strength of the low arm base portion 110 is less than 540 MPa, it is difficult to effectively secure the structural rigidity of the single-plate type low arm 100, and thus the thickness may be additionally increased. On the contrary, if the low arm base portion 110 When the tensile strength of exceeds 820MPa, the formability of the high tensile strength steel sheet may be deteriorated or the competitiveness of the product may be reduced due to the increased cost.

Therefore, the tensile strength of the low arm base 110 in the present invention is preferably limited in the range between 540 ~ 840 MPa.

The low arm base 110 preferably has a thickness of 2.0 to 4.0 mm.

If the thickness of the low arm base portion 110 is less than 2.0 mm, the self-weight reduction characteristics may be improved, but it is difficult to effectively secure the structural rigidity of the single plate type low arm 110.

On the contrary, if the thickness of the low arm base portion 110 exceeds 4.0 mm, the structural strength of the self is increased, and thus the durability of the product may be improved. However, the weight of the single plate type low arm 110 becomes excessively large, thereby reducing the weight of the vehicle. It can be counterproductive to the trend.

Therefore, the thickness of the low arm base portion 110 in the present invention is preferably limited in the range of 2.0 ~ 4.0 mm.

As shown in FIG. 4, the low arm base 110 has an arc-shaped link shape.

The single-plate low arm 100 according to the present invention is one of the main parts of the vehicle suspension system that connects the crossbeam (not shown) and the knuckle arm (not shown), and loads at the center of the arc of the low arm base portion 110. This tends to be concentrated and frequently cause breakage.

As a means for reinforcing this, in the present invention, the low arm reinforcing part 120 is applied.

The low arm reinforcement part 120 is a member that is coupled to the structural stiffness weak part of the above-described low arm base part 110 and plays a role of ensuring the structural strength of the overall single plate type low arm 100.

The low arm reinforcement part 120 is manufactured to be in close contact with the inner groove 114 of the low arm base part 110. In other words, the overall appearance of the low arm reinforcement unit 120 may be applied differently depending on the structural rigid weak part of the low arm base unit 110, and at the same time, its thickness and tension depending on the reinforcement strength required for the low arm base unit 110. Strength properties are also adjustable.

Particularly, in the case of the low arm reinforcement part 120, the lower arm reinforcement part 120 has a corresponding shape that is inserted into the arc center portion of the low arm base part 110 and fitted to each other, and protruding ends 112a and 112b of the low arm base part 110 are provided at both ends of the width. And reinforcing ends 122a and 122b protruding in the same shape to face to face contact.

At this time, in the case of the low arm reinforcement unit 120, the overall shape is molded and manufactured using a high-tensile steel sheet similarly to the low arm base unit 110, but unlike the low arm base unit 110, the list-like process is not processed In the reinforcing ends 122a and 122b, springback is generated in which bending deformation occurs outward.

The reinforcement ends 122a and 122b of the roam reinforcement part 120, which is caused by the springback, pressurize the inner side surfaces of the protruding ends 112a and 112b of the roam base part 110, thereby eliminating micro clearances from each other. By means of a close fit, the two parts can be fixedly united.

Referring to FIG. 5, the reinforcing end portions 122a and 122b of the roam reinforcement portion 120 where the springback has been generated, and the protruding end 112a of the roam base portion 110 where the springback is not generated because the springback process is performed in advance. The interference fit between 112b) can be confirmed.

As shown in Fig. 5, the reinforcement ends 122a and 122b having springbacks are urged to push out the protruding ends 112a and 112b which do not springback and firmly maintain dimensional accuracy. Shows.

Through this pressing mechanism, the reinforcing ends 122a and 122b are firmly fixed to the protruding ends 112a and 112b, whereby the roam reinforcing portion 120 is structurally reinforced in the inner local area of the roam base portion 110. Joined and fastened for

Subsequently, a material and a shape of the low arm reinforcement part 120 will be described with reference to FIG. 4.

The low arm reinforcement part 120 has a material characteristic of using a high tensile strength steel sheet as a material similar to the low arm base part 110, but aims to compensate for weak structural rigidity of the low arm base part 110. In order to perform this more effectively, it is desirable to have better tensile strength.

Therefore, the low arm reinforcing portion 120 according to the present invention may be made of a high tensile steel sheet having a tensile strength of 600 ~ 900 MPa as its material.

If the tensile strength of the low arm reinforcement portion 120 is less than 600 MPa, it is difficult to effectively exhibit the structural rigidity reinforcement effect on the local part that was structurally weak in the low arm base portion 110, and, conversely, the low arm reinforcement portion ( When the tensile strength of 120) exceeds 900MPa, the formability of the high tensile strength steel sheet may be deteriorated or the competitiveness of the product may be deteriorated due to the increased cost.

Therefore, the tensile strength of the low arm reinforcing portion 120 in the present invention is preferably limited in the range of 600 ~ 900 MPa.

In addition, the low arm reinforcement part 120 is preferably made of 1.2 to 2.0 times the thickness of the low arm base part 110 compared to the low arm base part 110.

If the thickness of the roam reinforcement portion 120 is too thick, as the weight of the end plate type roam 100 itself is increased may adversely affect the weight reduction of the vehicle, otherwise the thickness of the roam reinforcement portion 120 If is too thin, it may be difficult to fully realize its reinforcing effect.

Therefore, the thickness of the roam reinforcement portion 120 is not too thick compared to the thickness of the roam base portion 110, but not so thin that the structural reinforcement effect, as well as to prevent adverse effects due to weight increase It is preferable to be molded to a thickness of 1.2 to 2.0 times the level.

The low arm reinforcement unit 120 may be fixedly coupled to at least one or more at the site where the structural rigidity of the low arm base unit 110 is weak. However, when the number of the roam reinforcing portion 120 is increased, since the weight of the whole single plate-shaped roam 100 may be increased, it is preferable to apply the unit as much as possible as shown in FIG. 4. .

As described above, the roam reinforcement portion 120 that is forcibly fitted to each other due to the springback induction in the roam base portion 110 is not a form of joining parts by welding unlike the conventional, the fastening force, of course, Various problems due to breakage at the welding site can be effectively prevented, and in order to exert a better tightening force, additional additional fastening means can be further applied.

As can be seen with reference to Figure 4, the roam reinforcement portion 120 is fixed in the interference fit form in the low arm base portion 110 by using the spring back phenomenon, it is firmly fixed in the low arm base portion 110 It is.

However, in order to further exhibit a fastening force, a predetermined fastening part 130 may be further mounted on the joint portion of the low arm base part 110 and the low arm reinforcing part 120.

Here, the fastening part 130 may be a fastening bolt or a fastening rivet, or the like, but any other conventional fastening means may be used.

The fastening part 120 is fastened through the low arm base part 110 and the low arm reinforcement part 120 at the same time, thereby further strengthening the coalescing force between each other.

However, the fastening part 120 may be fastened by simultaneously passing through the low arm base part 110 and the low arm reinforcement part 120 at the inner groove of the low arm base part 110.

When the fastening part 120 is fastened through the protruding ends 112a and 112b of the low arm base part 110 and the reinforcing ends 122a and 122b of the low arm reinforcing part 120, This is because cracks are more easily generated at the fastening site due to the load concentration phenomenon.

And the number of installation of the fastening portion 120 is preferably at least two or more applied. In this embodiment, two fasteners 120 are used as shown in FIG. 4, but the present invention is merely exemplary and the present invention does not need to be limited to the number of fasteners 120.

Next, with reference to Figure 6 will be described a preferred embodiment of a method of manufacturing a single plate-shaped low-arm having an improved reinforcement structure using a spring back according to the present invention.

FIG. 6 is a flowchart illustrating a method of manufacturing a single plate type loam having an improved reinforcement structure using a springback according to an embodiment of the present invention.

Referring to FIG. 6, first, a low arm base part is formed by using a high tensile steel sheet (S100).

This step (S100), as a molding step of the low arm base portion, using a high tensile strength steel sheet having a tensile strength of 540 ~ 820 MPa, to form the low arm base portion to a thickness of 2.0 ~ 4.0 mm.

At this time, the shape of the moldable ro-arm base portion may be slightly differently applied to various embodiments according to the present invention. However, the shape of the ro-arm base is generally provided, and the end plate protrudes along the outer edge. And it can be manufactured in the form of a groove formed inward through the protruding end.

Next, a retrike process is performed to the molded low arm base part (S200).

This step (S200) is a step of performing a list-like process to improve the dimensional accuracy by preventing the springback phenomenon of the low-arm base portion formed in the previous step (S100).

Next, the low arm reinforcing portion is molded using a high tensile steel sheet (S300).

This step (S300) is a step of forming the low arm reinforcing part, by using a high tensile strength steel sheet having a tensile strength of 600 ~ 900 MPa, forming a low arm reinforcing part 1.2 to 2.0 times the thickness of the low arm base part to be.

However, unlike the above-described low arm base part, the low arm reinforcement part in this step (S300) does not perform a list-like after machining, which is to take full advantage of the springback phenomenon that may be caused in the low arm reinforcement part.

In this case, the shape of the moldable roam reinforcement may be differently applied to various embodiments according to the present invention. However, the shape of the roam reinforcement may be a shape corresponding to the shape of the roam base, which is manufactured in advance. It is preferable to be manufactured in the shape corresponding to the weak part of rigidity.

Next, the roam reinforcement part is inserted into and fixed to the structurally fragile part of the roam base part, and the spring is caused by the roam reinforcement part by using a spring back induced close fit (close fit) to the roam base part (S400).

In this step (S400), springback is not induced at the outer edge protruding end of the low arm base portion subjected to the re-listing process, and spring back is induced at the reinforcing end portion of the low-arm reinforcing portion which is not subjected to the re-listening process, thereby forcing a mutual fit. Fixed coalescence is achieved.

Through these previous steps (S100, S200, S300, S400), the low arm base and the low arm reinforcement are firmly fixed to each other and coalesced.

Furthermore, in order to reinforce the bonding force of the low arm reinforcing part that is forcibly fitted to the low arm base part, an additional fastening operation may be performed (S500).

The fastening operation in this step S500 is made possible by additionally fixing the bolt and riveting the combined area of the low arm base portion and the low arm reinforcement portion.

Through the above steps, the manufactured single plate type loam according to the present invention, the reinforcing piece for securing structural stiffness to the localized site where the concentration of the load is induced in the structure of the roll arm, but the spring back of the high tensile steel sheet ( By utilizing the spring back phenomenon, the reinforcing pieces are mutually coupled in a tight fit manner on the structurally weak areas of the low arm, and the fastening force is further strengthened by the fastening means, thereby increasing component durability. .

In the above it was described a preferred embodiment of a single plate type low-arm having an improved reinforcement structure using a spring back according to the present invention and a method of manufacturing the same.

It is to be understood that the above-described embodiments are illustrative in all aspects and should not be construed as limiting, the scope of the invention being indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

100: Roam
110: low arm base
120: low arm reinforcement
130: fastening part

Claims (18)

A low arm having an outer shape and having an end protruding along an outer edge thereof, and having a groove formed therein; And
The lower arm base is in close contact with the inner groove and has a shape that can be added, and is mutually close fit by a spring back of a reinforcing end provided to face the protruding end of the lower arm base part, thereby forming the lower arm base. It includes; roam reinforcement unit fixed to the unit;
The low arm base part and the low arm reinforcement part are made of a high tensile steel sheet, and the low arm base portion is made of a high tensile steel sheet, and is formed after a restriking process after forming, and springback occurs at the protruding end. Not,
The low arm reinforcing part is made of a high-strength steel sheet, but the re-trike (restrike) processing is not processed after molding, the low arm has an improved reinforcement structure using a spring back, characterized in that the spring back occurs at the reinforcement end.
delete delete delete The method of claim 1,
The low arm base portion,
Roam having an improved reinforcement structure using a spring back, characterized by having a tensile strength of 540 ~ 820 MPa.
The method of claim 1,
The low arm reinforcement,
Roam with improved reinforcement structure using a spring back, characterized in that having a tensile strength of 600 ~ 900 MPa.
The method of claim 1,
The low arm base portion,
Low arm with improved reinforcement structure using spring back, characterized in that the thickness of 2.0 ~ 4.0 mm.
The method of claim 1,
The low arm reinforcement,
Loam having an improved reinforcement structure by using a spring back, characterized in that made of 1.2 to 2.0 times the thickness of the low arm base portion.
The method of claim 1,
The low arm reinforcement,
Roam having an improved reinforcement structure by using a spring back is fixed to at least one of the structural rigidity of the roam base portion is weakly coupled to reinforce local structural strength on the roam base portion.
The method of claim 9,
The structurally fragile portion of the roam base portion to which the roam reinforcement portion is coupled is a roam having an improved reinforcement structure using a spring back, which is an arc center portion among all regions of the roam base portion having an arc-shaped link shape.
The method of claim 1,
Spring back, characterized in that further comprising a fastening portion which is fastened through the ro-arm base portion and the ro-arm reinforcement at the same time to further strengthen the coupling between the ro-arm base portion and the ro-arm reinforcement to be mutually interfitted and fixed coalescing Roam with improved reinforcement structure using.
The method of claim 11,
The fastening portion
The low arm has an improved reinforcement structure using a spring back, characterized in that the at least two through the inner groove of the ro arm base formed in close contact with the reinforcement portion is in close contact.
The method of claim 11,
The fastening portion
Loam having an improved reinforcement structure using a spring back, characterized in that the fastening bolt or fastening rivet.
(a) forming a low arm base part using a high tensile steel sheet;
(b) subjecting the molded low arm base portion to a restrike process;
(c) forming the low arm reinforcement using a high tensile steel sheet; And
(d) inserting and fixing the low arm reinforcement to the structurally weak part of the low arm base part, and forcing a close fit to the low arm base part using a spring back induced by the low arm reinforcement part; A method for producing a low arm having an improved reinforcement structure using a spring back.
15. The method of claim 14,
In the step (c)
The molded low arm reinforcement portion, the method of manufacturing a low arm with an improved reinforcement structure using a spring back, characterized in that not performing a separate wrist-like process to induce the occurrence of spring back.
15. The method of claim 14,
In the step (d)
Springback is not induced at the outer edge protruding end of the low arm base portion subjected to the wrist-like reclamation, and springback is induced at the reinforcement end of the low arm reinforcement portion which is not subjected to the wrist reclamation process, so that a fixed coalescing is made through mutual interference fit. Method for producing a low arm having an improved reinforcement structure using a spring back.
15. The method of claim 14,
After the step (d)
(e) performing an additional fastening operation for strengthening coupling between the ro-arm base portion and the ro-arm reinforcement which are mutually interfitted; and further comprising an improved reinforcement structure using a spring back. Process for producing roam.
The method of claim 17,
In the step (e)
The fastening operation is a method of manufacturing a low arm with an improved reinforcement structure using a spring back, characterized in that for fixing the bolt or rivets on the combined area of the low arm base and the low arm reinforcement.

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