KR20200065445A - Manufacturing method for panel of vehicle - Google Patents

Abstract

The present invention provides a manufacturing method of a plate for a vehicle which can improve the size precision of a final product. The manufacturing method of a plate for a vehicle comprises: a drawing process of pressing a cut plate to protrude and/or indent in a set side on the surface of the plate to produce a first formed product of a set shape; an edge trimming process of cutting the first formed product which has undergone the drawing process along an edge trimming line to form a fixed gap on a final trimming line of a final product to produce a second formed product; a restriking process of machining to at least remove elastic recovery and springback in the second formed product which has undergone the edge trimming process; and a final trimming process of cutting a formed product after the restriking process in the final trimming line.

Description

Manufacturing method of plate for vehicles{MANUFACTURING METHOD FOR PANEL OF VEHICLE}

The present invention relates to a method for manufacturing a plate material for a vehicle with improved dimensional accuracy.

It should be noted that the contents described in this section merely provide background information about the present invention and do not constitute the prior art.

Parts using a metal plate are usually produced in mass through a continuous molding process using a press and a mold.

In recent years, as the need for weight reduction of parts increases, the use of lightweight metal plates has increased.

In order to overcome the insufficient moldability of the lightweight metal plate, the molding process is sometimes performed at warm temperatures.

However, since the application is not yet active, the warm forming process of lightweight metal is not widely used, and in most cases, the aluminum sheet can be molded at room temperature.

After molding, the dimensions of the parts are measured. The dimensional accuracy of the parts is a very important factor for assembly with other parts.

One of the factors that have a great influence on the dimensional accuracy of parts in the molding process is a springback or elastic recovery phenomenon.

In the conventional case, many efforts have been made to reduce springback or elastic recovery in the molding process, and various methods have been developed, but in most cases, the result of springback is checked by trial and error, and molding is performed based on this. A method of repeating this process while inversely modifying the mold surface shape of the process is widely used.

However, this method has a problem that it takes a lot of time and money.

KR 10-1450821

As an aspect of the present invention, an object of the present invention is to provide a method for manufacturing a plate material for a vehicle, which is capable of improving the dimensional accuracy of a final product by preventing an increase in the dimensional error occurring during the molding process.

As one aspect for achieving the above object, the present invention is a drawing process for processing a first molded product of a set shape by pressing and/or intruding to a set dimension on the surface of the plate by pressing the cut plate; An outer trimming process of cutting the first molded product that has undergone the drawing process along the outer trimming line so that a certain gap is formed in the final trimming line of the final product; A list riking process of processing to at least remove springback or elastic recovery occurring in the second molded product that has undergone the outer trimming process; And a final trimming process of cutting the molded product after the list-like process into a final trimming line.

Preferably, the plate material is composed of a magnesium plate material, and the drawing process and the list-writing process may be performed in a range of 130°C or more and 260°C or less.

Preferably, the list riking process may be carried out within a range of ± 50 °C of the drawing process temperature conditions.

Preferably, the drawing process and the list-listing process may be performed under the same temperature conditions.

Preferably, a piercing process of forming a piercing hole having a shape set in the second molded article and processing the third molded article after the list-like process may be further included.

Preferably, in the outer trimming process, the first molded product may be cut so that the same gap is formed in the final trimming line in the range of 3 times or more and 10 times or less the thickness of the plate.

Preferably, the final product made of a plate material may be an inner panel of a vehicle hood.

According to an embodiment of the present invention, it is possible to prevent the increase in the dimensional error occurring during the forming process of the plate material, thereby improving the dimensional accuracy of the final product.

1 is a view showing a method of manufacturing a vehicle plate according to an embodiment of the present invention.
2 is a view showing a drawing process of a method for manufacturing a plate material for a vehicle according to an embodiment of the present invention.
3 is a view showing an outer trimming process of a method for manufacturing a vehicle plate according to an embodiment of the present invention.
4 is a view showing a list scribing process of a method for manufacturing a plate material for a vehicle according to an embodiment of the present invention.
5 is a view showing a piercing process and a final trimming process of a method for manufacturing a vehicle plate according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. The shape and size of elements in the drawings may be exaggerated for a more clear description.

Hereinafter, a method of manufacturing a plate material for a vehicle according to an embodiment of the present invention will be described in detail with reference to the drawings.

1 to 5, a method of manufacturing a vehicle plate according to an embodiment of the present invention includes a drawing process (S10), an outer trimming process (S20), a list licking process (S30), and a final trimming process (S50). It may include, and may further include a piercing process (S40).

Referring to FIG. 1, a method of manufacturing a vehicle plate material includes a drawing process (S10) of processing a first molded product 20 having a set shape by pressing and/or intruding a cut plate material to a set dimension on the surface of the plate material, The first molded product 20 that has been subjected to the drawing process (S10) is cut along the outer trimming line L1 to form a constant gap M in the final trimming line L2 of the final product 40. 30) the outer trimming process to process (S20), and the outer trimming process (S20) to the second molded product 30, the spring back (spring back) or elastic recovery (Elastic recovery) at least to remove the processing List Liking Process (S30); And, it may include a final trimming process (S50) for cutting the molded article after the list riking process (S30) to the final trimming line (L2).

The plate material to which the method for manufacturing a vehicle plate material of the present invention is applied may be composed of a metal plate material or a light metal plate material.

For example, the lightweight metal plate to which the method for manufacturing a vehicle plate according to the present invention is applied may be composed of a magnesium plate.

In order to minimize spring back or elastic recovery, the plate can be warm formed.

Referring to Figure 2, the drawing process (S10) can be processed into a first molded product 20 of a set shape by pressing and intruding to a set dimension on the surface of the plate by pressing the plate cut into a drawing mold.

Before the drawing process (S10), a plate cutting process may be performed to cut the plate to a certain size.

The drawing process S10 may be processed into a first molded product 20 having a set shape in which a plate material is protruded and/or inserted by pressurization of the upper drawing mold and the lower drawing mold.

In the drawing process (S10), the plate material may be warm formed.

Referring to FIG. 3, the outer trimming process (S20) is a process of cutting along the outer trimming line L1 that is larger than the final trimming line L2 of the final part of the actual part by using a mold or a laser device.

In the outer trimming process (S20), the first molded product 20 is cut with a mold or a laser device, and the gap M is a constant separation distance from the final trimming line L2 of the final product 40 to the outer trimming line L1. The second molded article 30 may be processed to form this.

By forming the gap (M) between the outer trimming line (L1) and the final trimming line (L2) by the outer trimming process (S20), the introduction of an additional process to correct the dimensional change of the product due to springback or elastic recovery It has the effect of becoming possible.

Referring to FIG. 4, the list riking process (S30) is a process of reprocessing to remove springback or elastic recovery generated in the second molded product 30.

List riking process (S30) is a process of reshaping the molded product to correct the shape and dimensions.

The spring back is a phenomenon in which the amount of bending is reduced due to the elastic action of bending the material in the bending process of the plastic material and then restoring it to the original state where pressure is removed.

In the case of the present invention, the list riking process (S30) is a drawing process (S10), the outer trimming process (S20) by removing the deformation caused by springback or elastic recovery generated in the second molded article 30, the dimensions of the product It is possible to improve the dimensional accuracy of the final product 40 by preventing an increase in error.

In one example, list riking may be an operation for correcting internal stress and deformation.

After the drawing process (S10) and the outer trimming process (S20), the plate material formed into the set shape is returned to its original shape by a springback or elastic recovery phenomenon. Can be corrected.

The list riking process (S30) may remove the springback phenomenon, which is a decrease in the amount of bending generated in the second molded product 30 through the outer trimming process (S20) with a list riking mold.

The present invention, before the final trimming process (S50), by performing the outer trimming process (S20) and list riking process (S30), it is possible to improve the dimensional accuracy by minimizing the dimensional change of the product due to springback or elastic recovery It works.

In one example, the list-driving process (S30) may be performed as the process immediately following the outer trimming process (S20).

The final trimming process (S50) may be performed after the list-like process (S30).

For example, the piercing process (S40), the flanging process, and the final trimming process (S50) may be performed after the list-like process (S30).

This is because the list riking process (S30) is performed for the purpose of removing the springback, and thus the dimensions of the molded product and the like are largely changed before and after the process.

Therefore, if the piercing process (S40) forming the piercing hole and the final trimming process (S50) cutting along the final trimming line (L2) are performed at all stages of the list-driving process (S30), the list-driving process (S30) This is because the possibility that the position of the piercing hole P or the dimension of the edge portion may be distorted by) may be greatly increased, and thus the dimensional accuracy of the final product 40 may be significantly reduced.

Referring to FIG. 5, the final trimming process (S50) is a process of cutting a molded product after the list-driving process (S30) into a final trimming line (L2).

The molded product introduced into the final trimming process (S50), that is, the molded product after the list riking process (S30), is either a second molded product 30 that has not been subjected to the piercing process (S40) or a third molded product that has been subjected to the piercing process (S40). It can be one.

In one example, the final trimming process (S50) may cut the outer periphery of the second molded product 30 along the final trimming line L2 to be processed into the final product 40.

As another example, when the piercing process (S40) is added between the list-driving process (S30) and the final trimming process (S50), the outer edge of the third molded product formed through the piercing process (S40) is the final trimming line (L2). It can be cut along to be processed into the final product (40).

The plate material is made of a magnesium plate material, and the drawing process (S10) and the list-listing process (S30) may be performed in a range of 130°C or more and 260°C or less.

When the magnesium sheet is warm-formed, the springback phenomenon may be reduced.

In one example, the plate material is composed of a magnesium plate material, and may be warm molded in a range of 130°C or higher and 260°C or lower.

In order to minimize spring back or elastic recovery, the sheet material should be warm molded in the range of 130°C to 260°C.

As described above, the reason why the temperature of the warm forming is limited to 130° C. or higher is that excessive springback occurs when molding is performed at a temperature lower than 130° C.

In addition, the reason why the temperature of the warm forming is limited to 260° C. or less is that when molding is performed at a temperature higher than 260° C., the dimensional error of the product may increase as the amount of thermal deformation increases with temperature. Because there is.

The method of manufacturing a sheet material for a vehicle may be performed in the range of ±50°C of the temperature condition of the drawing process (S10) in the list-listing process (S30).

This is because if the temperature is high or low so that the temperature in the list riking process (S30) deviates from the temperature of the drawing process (S10) by ± 50°C, there is a possibility that dimensional errors may occur even after the list riking.

In one example, the drawing process (S10) is performed at 200°C, and the risk-liking process may be performed in a range of 150°C or more and 250°C or less.

The drawing process (S10) and the list-listing process (S30) may be performed under the same temperature conditions.

The drawing process (S10) and the list-listing process (S30) may be performed in a range of 130° C. or more and 260° C. or less, and the drawing process (S10) and list-listing process (S30) may be processed under the same temperature conditions.

The drawing process (S10) and the list-listing process (S30) may be performed at the same temperature.

In the drawing process (S10), the plate material may be drawn into the drawing mold while being heated to a set temperature of warm forming (eg, 200°C).

At this time, the drawing mold may also be processed into the first molded product 20 having a set shape by pressing the heated plate material in a state heated to a set temperature of warm forming (eg, 200° C.).

In the list-listing process (S30), the plate material may be introduced into the list-listing mold while being heated to a set temperature of warm forming (eg, 200°C).

At this time, the list riking mold may also be processed into a first molded product 20 having a set shape by pressing a heated component in a state heated to a set temperature of warm forming (eg, 200° C.).

For example, the drawing process (S10) and the list-listing process (S30) may be performed at a temperature of 200°C.

The drawing process (S10) and the list-listing process (S30) may be performed at different temperature conditions.

In one example, the drawing process (S10) is carried out in the range of 130 °C or more and 260 °C or less, and the risk-risking process can be carried out in the range of 150 °C or more and 250 °C or less.

Referring to FIG. 1, a method of manufacturing a plate for a vehicle includes a piercing process (S40) in which a piercing hole (P) having a shape set in the second molded product 30 is formed and then processed into a third molded product after the list-writing process (S30). It may further include.

In the piercing process (S40), the piercing hole (P) of the shape set in the second molded product 30 in which the springback deformation is removed in the list riking process (S30) is processed into a third molded product, and in the final trimming process (S50) The outer part of the third molded product may be cut along the final trimming line to be processed into the final product 40.

In the outer trimming process (S20), the first molded product 20 is formed so that the same gap M is formed in the range of 3 times or more of the thickness T of the plate or 10 times or less of the thickness T of the plate in the final trimming line L2. ) Can be cut.

In the outer trimming process, it may be desirable that the gap M between the outer trimming line L1 and the final trimming line L2 of the actual component is set to a range of 3 to 10 times the thickness of the plate. .

First, since the springback or elastic recovery of the molded product is inversely proportional to the product thickness, the thickness (T) of the plate was set as the reference dimension of the gap (M).

As described above, the reason for forming the outer trimming line L1 in the final trimming line L2 at least three times the thickness of the plate material is that the gap between the final trimming line L2 and the outer trimming line L1 If M) is less than 3 times the thickness of the plate, it is difficult to match the exact trimming line to the molded product that has already undergone springback after molding, and it is possible that the outer trimming line (L1) will invade the final trimming line (L2), which is the actual part line. Because there is a problem.

In addition, the reason for forming the outer trimming line L1 in the final trimming line L2 to be 10 times or less the thickness of the plate material is the gap between the final trimming line L2 and the outer trimming line L1. This is because when M) exceeds 10 times the thickness of the plate, the number of plates cut out during the final trimming process increases excessively, and the possibility of further deformation due to elastic recovery increases.

More preferably, the plate material is composed of a magnesium plate material having a thickness in the range of 0.5 to 2.0mm, and the outer trimming process (S20) is three or more times of the plate material thickness T in the final trimming line L2. The first molded product 20 may be cut into a second molded product 30 so that the same gap M is formed within a range of 5 times or less of the thickness T.

The final product 40 made of a plate material in the method of manufacturing a plate material for a vehicle may be an inner panel of a vehicle hood.

The inner panel of the vehicle hood may be combined with the outer panel of the vehicle hood.

A magnesium plate may be used as an inner panel for a vehicle hood, and a steel material such as steel may be used as an outer panel for a vehicle hood.

At this time, the outer panel of the vehicle hood may be made of high-strength steel.

Hereinafter, the method for manufacturing a vehicle plate material of the present invention is performed by performing an outer trimming process (S20) and a list-driving process (S30) by a warm forming method, thereby manufacturing a vehicle plate material of the present invention in order to confirm the resulting dimensional correction effect. The values of the flush according to the method and the method of manufacturing the vehicle plate for comparison are compared with each other.

As a method of measuring the dimensional accuracy, a method of measuring the flush of the final product 40 is utilized, where the value of the flush is the final product 40 in design and the final product actually molded (40). ).

In the case of a method for manufacturing a vehicle plate material for comparison, in order to compare with the method for manufacturing a vehicle plate material of the present invention, the rest of the conditions of the present invention are the same, and the outer trimming process (S20) and list riking process (S30) of the present invention are performed. Omitted and the final product 40 was molded.

First, a method of manufacturing a plate material for a vehicle according to an embodiment of the present invention will be described as an example.

As an example, a detailed look at each process of the present invention is as follows.

The drawing process S10 may be performed at 200°C.

After the plate material is heated to 200°C, it is transferred to a drawing mold heated to 200°C to perform molding.

2 shows the shape of the first molded body molded in the drawing process S10.

After the drawing process (S10), an outer trimming process (S20) is performed.

The outer trimming process (S20) is carried out along the outer trimming line L1 of the first molded body, and in this embodiment, 5 mm, which is about 4 times the material thickness (1.2 mm) according to the above-mentioned outline of the outer gap (M). A second molded body was formed by trimming the outer line with the gap (M).

3, the shape of the second molded body cut along the outer trimming line L1 in the outer trimming process S20 is illustrated.

After the outer trimming process (S20), a list-liking process (S30) is performed.

The list riking process (S30) is performed using a list riking mold, and the temperature of the list riking mold may be set to 200° C., which is the same temperature as the drawing mold to the drawing process (S10).

At this time, the temperature of the first molded article 20 introduced into the list riking process (S30) was also maintained at 200°C, which is the same as the mold temperature.

In order to confirm the influence of the temperature and the proper temperature in the list-listing process (S30), a list-listing process (S30) was performed not only at 200°C, but also at 150°C and 250°C.

After listing, the flush of the second molded body was measured at a number of points on the outermost line of the second molded product 30 to check the dimensions.

As a result of the measurement, the maximum flush was measured to be 1 mm or less under 200°C list riking conditions, but the maximum flush was measured to be 4 mm or more at 150°C and 250°C.

Therefore, the temperature of the list riking process (S30) should be the same as the temperature of the drawing process (S10), and it was confirmed that the component dimensional error is minimized after the list riking.

After the list riking process (S30), the piercing process (S40) and final trimming were performed.

The final process, the piercing process (S40) and the final trimming process (S50), is performed at room temperature.

However, there is no problem even when it is carried out at 200°C. However, when the last process, the piercing process (S40) and the final trimming process (S50), is performed at 200°C, it is necessary to correct the dimensions of the mold and the like in consideration of the temperature of the last process.

5, a piercing hole P is formed, and the shape of the final product 40 cut along the final trimming line is shown.

The dimensions of the final product 40 after the final trimming process (S50) were measured in order to confirm the effect of removing the springback and the dimensional correction effect of the vehicle plate manufacturing method according to the present invention.

The dimensions of the final product 40 were measured at a number of locations at the edge of the part, and the maximum flush value was 1.1 mm as a result of the measurement.

In the case of a method for manufacturing a vehicle plate material for comparison, in order to compare with the method for manufacturing a vehicle plate material of the present invention, the above-described conditions and the rest of the conditions are the same, and the outer trimming process (S20) and list-listing process (S30) of the present invention ) Was omitted and the final product 40 was molded.

The dimensions of the final product 40 were measured at a number of locations at the edge of the part, and as a result, the maximum flush value at the edge was measured to be 4 mm or more.

The method for manufacturing a vehicle plate material according to the present invention was confirmed to have a dimension correction effect of 3 mm or more through a combination of an outer trimming process (S20) and a list riking process (S30), compared to a method for manufacturing a vehicle plate material for comparison.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and it is possible that various modifications and variations are possible without departing from the technical spirit of the present invention as set forth in the claims. It will be apparent to those of ordinary skill in the field.

20: first molded article 30: second molded article
40: Final product L1: Outer trimming line
L2: Final trimming line M: Clearance
P: Piercing hole T: Plate thickness
S10: Drawing process S20: Outline trimming process
S30: List liking process S40: Piercing process
S50: Final trimming process

Claims (7)

A drawing process in which the cut sheet is pressed to protrude and/or intrude into a set dimension from the surface of the sheet to form a first molded product having a set shape;
An outer trimming process of cutting the first molded product that has undergone the drawing process along the outer trimming line to form a constant gap in the final trimming line of the final product;
A list riking process of processing to at least remove springback or elastic recovery occurring in the second molded product that has undergone the outer trimming process; And,
And a final trimming process of cutting the molded product after the list-like process into a final trimming line.
According to claim 1,
The plate material is made of a magnesium plate material, and the drawing process and the re-listing process are performed in a range of 130° C. or more and 260° C. or less.
According to claim 2,
The list riking process is a method of manufacturing a sheet material for a vehicle, characterized in that carried out within a range of ± 50 ℃ of the drawing process temperature conditions.
According to claim 2,
The drawing process and the list-listing process is a method of manufacturing a plate for a vehicle, characterized in that carried out under the same temperature conditions.
According to claim 1,
And a piercing process of forming a piercing hole having a shape set in the second molded product and processing the third molded product after the list-like process.
The method of claim 1, wherein the outer trimming process,
A method of manufacturing a sheet material for a vehicle, wherein the first molded product is cut so that the same gap is formed in a range of 3 times or more of the thickness of the sheet material and 10 times or less of the thickness of the sheet material in the final trimming line.
According to claim 1,
The final product made of the plate material is a vehicle plate manufacturing method, characterized in that the inner panel of the vehicle hood.

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