KR20240040290A - Method for forging integral pipe nut for electric vehicle battery platform and manufacturing device thereof - Google Patents

Abstract

The present invention relates to a forging method and manufacturing device for an integrated pipe nut for an electric vehicle battery platform.
The present invention includes preparing a raw material (M0) (S100); Extrusion forging molding the prepared raw material (-0) into the primary molding (M1) (S200); Extrusion forging molding the primary molding (M1) into a secondary molding (-2) (S300); A step (400) of molding the secondary molded product (-2) into a tertiary molded product (M3); An integrated fight nut (PN) for an electric vehicle battery platform in which the flange portion 44 and the nut portion 47 are formed integrally by completing the third molding (M3) into a fight nut (PN) is provided.

Description

Method for forging integral pipe nut for electric vehicle battery platform and manufacturing device thereof}

The present invention is an electric vehicle battery that can reduce manufacturing defects and improve productivity by manufacturing the flange portion and the nut portion as an integrated pipe nut, which consists of a flange portion and a nut portion and secures the battery and cover to the battery platform of an electric vehicle. It relates to a forging method and manufacturing device for an integrated pipe nut for a platform.

Unlike internal combustion engine platforms, the battery platform of an electric vehicle can have a flat floor, and the battery pack itself laid on the bottom of the car body can be used to increase rigidity, and the space occupied by the engine, transmission, and fuel tank is greatly reduced. It allows for innovative space implementation that can increase the utilization of interior space, and has the feature of lightening the weight of the car.

As shown in Figures 1 and 2, the battery platform 400 for an electric vehicle is installed on the upper part of the lower frame 410 of the car body to accommodate a plurality of battery modules. Specifically, inside the battery platform 400, a plurality of partition walls (not shown) with a square cross-section are arranged in the longitudinal direction or width direction of the vehicle body to partition the internal space, and to store the battery module in the partitioned space. Next, the upper part of the platform is closed with a cover 420, which is usually mounted at approximately 8 locations using pipe nuts 500 to firmly connect the battery and the vehicle body.

By increasing the rigidity of the battery and vehicle body connection while installing the battery platform, battery safety in the event of a collision can also be improved. The mounting structure using the pipe nut 500 as shown above is fastened with a long bolt 430 from the bottom of the battery to the inside of the bottom to secure the battery. It not only maximizes the rigidity of the body and body combination, but also reduces vibration and noise while driving, resulting in additional advantages such as improved performance and ride comfort.

In the conventional pipe nut 500, the flange part and the nut part are manufactured separately, the flange part and the nut part are welded, and then fixed to the bottom of the battery platform 400 so that the flange part is at the bottom and the nut part is at the top, and the platform ( 400), the cover 420 was placed on the upper part, and then the long bolt 430 was fastened to the nut portion of the pipe nut 500.

This structure in which the flange portion and the nut portion are separated and fused together increases the number of processes required for fusion bonding, and there is a risk of dimensional deformation or fatigue failure of the weld joint due to the fusion operation.

In addition, the pipe nut molding in which the flange part and the nut part are separated and fused together undergoes a hardening heat treatment process to improve the bonding strength of the battery platform. However, thermal deformation may occur in the final hardening heat treatment process, making it difficult to fasten the bolt. There was a case where it happened.

In this way, the conventional method of manufacturing the flange part and the nut part separately and fusing them together was implemented during the research and development stage of electric vehicles at a time when the flange nut did not require much demand.

However, the research and development of electric vehicles has made rapid progress, and electric vehicles will form the mainstream of the automobile market in the future. Therefore, there is a need to efficiently supply pipe nuts for electric vehicle battery platforms with precision parts with high rigidity.

KR 10-2022-0089063 A (2022. 06. 28) KR 10-1209935 B (2012. 12. 03.) KR 10-1997-0039181 A (1997. 07. 24.) KR 20-0127942 U (1998. 07. 29.)

The object of the present invention is to provide an integrated pipe nut that can prevent dimensional deformation due to fusion work or fatigue failure of welded joints by forming the flange portion and the nut portion integrally in manufacturing a pipe nut for an electric vehicle battery platform. The purpose is to provide a forging method and a manufacturing device thereof.

Another object of the present invention is to manufacture a pipe nut for an electric vehicle battery platform by curing and heat-treating a molded product in which the flange portion and the nut portion are integrally formed and then performing a trimming process to prevent deformation due to the curing heat treatment. To provide a method for forging an integrated pipe nut for a battery platform.

The purpose of the present invention and its technical problems are not limited to the technical problems described above. Therefore, other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

The technical features of the integrated pipe nut forging method for an electric vehicle battery platform to achieve the intended purpose of the present invention are an electric vehicle consisting of a flange portion 44 mounted on the battery platform and a nut portion 47 to which a bolt is fastened. When manufacturing a pipe nut (PN) for a battery platform, the flange portion and the nut portion are manufactured by forging integrally.

The forging method according to the technical features of the present invention involves forming a blank 40 that is cylindrical and hollow in the axial direction, or using a raw material (M0) in which a blank 40 that is hollow in the axial direction is not formed. A preparation step (S100); Using the first extrusion forging mold 10 equipped with the primary extrusion forging die 130 and the primary extrusion forging punch 150, except for a certain upper section of the raw material M0, the lower part thereof A thick cylindrical portion 41 for forming the flange portion 44 by extrusion, and an extrusion molding portion extending from the thick cylindrical portion 41 to form a step with a reduced cross-section in order to mold the nut portion 47. A first molding (M1) extrusion forging forming step (S200) of forming (42); Using the second extrusion forging mold 20 provided with the secondary extrusion forging die 230 and the secondary extrusion forging punch 250, the upper center of the thick cylindrical portion 41 is formed from the primary molding M1. A flange portion 44 is formed from the upper outer circumferential surface of the thick cylindrical portion 41 while forming an upper extension portion 43 through which the blank 40 is expanded, and a flange portion 44 is formed from the lower portion of the blank 40 of the extrusion molding portion 42. Including the extrusion forging forming step (S300) of the secondary molding (M2) of forming the lower extension portion 45 to form the nut portion 46, the flange portion 44 and the nut portion 47 are formed integrally. It includes becoming.

According to the forging method according to the technical features of the present invention, the step (b200) of extrusion forging the primary molding (M1) is performed when the raw material (M0) has a blank 40 that is hollow in the axial direction, Forging the extrusion molding part 42 by forward extrusion, and when there is no axial hollow blank 40 in the raw material M0, forging the extrusion molding part 42 by backward extrusion. .

The forging method according to the technical features of the present invention removes the scrap 46 generated during forming the flange portion 44 from the secondary molding (M2) after the forging forming step (S300) of the secondary molding (M2). To do this, a trimming process is further included (S400).

The forging method according to the technical features of the present invention includes the steps of selectively softening heat treatment of the raw material (M0) and the primary molding (M1), and lubricating the softening heat treated raw material (M0) or molding (M1). It optionally further includes a step of coating treatment and a step of heat treatment to enhance hardness before trimming the secondary molding (M2).

According to the forging method according to the technical features of the present invention, the first extrusion forging die 130 and the first guide post 101 are fixed to the upper part of the first lower plate 100 in the first extrusion forging mold 10, A primary extrusion forging punch 150 is fixed to the lower part of the first upper plate 110, and the primary extrusion forging punch 150 is fixed between the first lower plate 100 and the first upper plate 110. The first punch holder 141 is fixed and includes a first movable plate 120 positioned to be raised and lowered from the upper part of the first guide post 101 toward the primary extrusion forging die 130, and the 1 The secondary extrusion forging punch 150 includes an upper center punch 151 extending vertically downward from the lower center of the first punch holder 141 and inserted into the blank 40 of the raw material M0; It is formed to extend cylindrically from the lower part of the first punch holder 141, surrounding the outside of the upper center punch 151, and presses the upper part of the raw material (M0) inputted into the first extrusion forging die 130 to form a cylindrical shape. It includes a first upper pressure punch 152 for forming a primary molding (M1) having a cylinder portion 41 and an extrusion molding portion 42, and an ejecting punch formed at the lower portion of the primary extrusion forging die 130. It includes that the tool 160 discharges the primary molded product (M1) from the primary extrusion forging die 130.

According to the forging method according to the technical features of the present invention, the second extrusion forging die 20 and the second extrusion forging die 230 and the second guide post 201 are fixed to the upper part of the second lower plate 200. , a secondary extrusion forging punch 250 is fixed to the lower part of the second upper plate 210, and a second punch holder 241 is fixed between the second lower plate 200 and the second upper plate 210. It includes a second movable plate 220 positioned to be lifted up and down on the second guide post 201, and the secondary extrusion forging die 230 is located at the upper center of the second lower plate 200. Formed as a space into which the primary molded product (M1) is input, a secondary molded product (M2) is provided with an upper extension portion 43, a flange portion 44, and a lower expansion portion 45 from the input primary molded product M1. is formed, and the secondary extrusion forging punch 250 extends vertically downward from the lower center of the second punch holder 241 to form an upper extension portion 43 and a flange portion formed on the primary molding (M1). The second upper pressure punch 251 forming (44) and the extrusion molding portion of the primary molding (M1) input into the secondary extrusion forging die 230 at the upper center of the second lower plate 200 ( 42) It includes a lower center punch 252 that is inserted into the internal blank 40 to enable the lower expansion portion 45 to be formed. After the secondary molding M2 is formed, the second upper pressure punch is inserted into the inner blank 40. As 251 rises, the lower center punches.

The technical feature of the device for forging an integrated pipe nut for an electric vehicle battery platform to achieve the intended purpose of the present invention is an electric vehicle consisting of a flange portion 44 mounted on the battery platform and a nut portion 47 to which a bolt is fastened. A device for manufacturing a pipe nut (PN) for an automobile battery platform, comprising: first extrusion forging to form a primary molding (M1) having a thick cylindrical portion (41) and an extrusion molding portion (42) from a raw material (M0) A second extrusion forging mold forming a mold 10 and a secondary molding M2 having an upper extension 43, a flange portion 44, and a lower expansion portion 45 from the primary molding M1. (20) is included.

According to the technical features of the present invention, the first extrusion forging mold 10 includes a primary extrusion forging die 130 formed on the first lower plate 100; A primary extrusion forging punch 150 fixed to the lower part of the first upper plate 110; It consists of a first movable plate (120) on which the first punch holder (01) is fixed to the first guide post (120) between the first lower plate (100) and the first upper plate (110) and can be raised and lowered. The primary extrusion forging die 130 includes a receiving portion 131 located at the upper center of the lower plate 100 into which the raw material M0 is input; A primary molding (M1) having a thick cylindrical portion (41) and an extrusion molding portion (42) is formed from the raw material (M0), which is formed as a space extending downward of the receiving portion (131) and is pushed in by pressing force. It includes a primary forming part 132, and the primary extrusion forging punch 150 extends vertically downward from the lower center of the first punch holder 141 in the axial direction formed in the raw material M0. an upper center punch (151) inserted into the hollow blank (40); It is formed to extend cylindrically from the lower part of the first punch holder 141, surrounding the outside of the upper center punch 151, and presses the upper part of the raw material (M0) inputted into the first extrusion forging die 130 to form a cylindrical shape. a first upper pressure punch (152) for forming a primary molding (M1) having a cylinder portion (41) and an extrusion molding portion (42); It includes an ejecting tool 160 for ejecting the primary molded product (M1) from the primary extrusion forging die 130.

According to the technical features of the present invention, the second extrusion forging mold 20 includes a secondary extrusion forging die 230 formed on the second lower plate 200; a secondary extrusion forging punch 250 fixed to the lower part of the second upper plate 210; It consists of a second movable plate 220 on which the second punch holder 241 is fixed to the second guide post 201 between the second lower plate 200 and the second upper plate 210 and is positioned to be raised and lowered. The secondary extrusion forging die 230 is located at the upper center of the second lower plate 200, into which the primary molded product M1 is input, and from the lower part of the blank 40 of the input primary molded product M1. a secondary molding part 231 inserted into the blank 40 and forming a lower expansion part 45; It includes a two-stage step portion 232 forming an upper extension portion 43 and a flange portion 44, and the secondary extrusion forging punch 250 is vertically positioned from the lower center of the second punch holder (). a second upper pressure punch 251 extending downward to form an upper expansion portion 43 and a flange portion 44 on the primary molding (M1) inputted into the secondary extrusion forging die 230; It is inserted into the blank 40 inside the extrusion molding part 42 of the primary molding (M1) inputted into the secondary extrusion forging die 230 at the upper center of the second lower plate 200 to form a lower extension part 45. ), and after the secondary molding (M2) is formed, the lower center punch 252 rises as the upper second upper pressure punch 251 rises and is formed. This includes being able to eject the secondary molding (M2).

According to the technical features of the present invention, the device for manufacturing the pipe nut (PN) for the electric vehicle battery platform is a second molding device (M2) to remove the scrap 46 formed on the flange portion 44 of the secondary molding (M2). It further includes a trimming mold 30 from the extrusion forging mold 20.

According to the technical features of the present invention, the trimming mold 30 includes a trimming die 330 formed on the third lower plate 300 and into which the secondary molding (M2) is input; a trimming punch 350 that is fixed to the lower part of the third upper plate 310 and removes the scrap 46 by pressing the boundary between the flange portion 44 of the injected secondary molding product M2 and the scrap 46; A third punch holder 341 for fixing the trimming punch 350 is fixed between the third lower plate 300 and the third upper plate 310 so that the trimming punch 350 can perform the trimming operation. It further includes a third movable plate 320 that can be raised and lowered on the guide post 301.

According to the present invention, by forming the flange portion and the nut portion of the pipe nut of the electric vehicle battery platform by using a cold forging method so that the nut portion is integrated by extrusion forging, the hard particle structure formed by extrusion forging has strong mechanical properties such as bending strength, making a high-strength pipe. In order to obtain a nut, a small amount of expensive alloy is required from the raw material, and by preventing shrinkage and deformation due to internal cavities and heat in the metal structure, it is possible to provide high-quality pipe nuts with high dimensional precision and a beautiful surface, and can be used for electric vehicles. Depending on demand, mass production is also possible.

1 is a perspective view of an electric vehicle battery platform to which the present invention is applied installed on the lower frame of a vehicle.
Figure 2 is a plan view of the electric vehicle battery platform 3 to which the present invention is applied installed on the lower frame of the vehicle.
Figure 3 is a partially cut-away perspective view showing the state of the process in which the material is molded and manufactured according to the present invention.
(a) is a partially cut perspective view of the raw material (M0)
(b) is a partially cut perspective view of the first molded product (M1)
(c) is a partially cut perspective view of the second molded product (M2)
(d) is a partially cut perspective view of the third molded product (M3)
(e) is a partially cut-away perspective view of the manufactured pipe nut.
Figure 4 is a process flow chart showing the process of manufacturing the pipe nut of the present invention
Figure 5 is a cross-sectional view of the first extrusion forging mold of the present invention,
(a) is a cross-sectional view
(b) is an enlarged cross-sectional view of the main part
Figure 6 is a cross-sectional view of the second extrusion forging mold of the present invention,
(a) is a cross-sectional view
(b) is an enlarged cross-sectional view of the main part
Figure 7 is a cross-sectional view of the trimming mold of the present invention,
(a) is a cross-sectional view
(b) is an enlarged cross-sectional view of the main part

The features and advantages of the present invention can be understood more clearly by looking at the embodiments illustrated in the accompanying drawings.

The application of the present invention is not limited by the configuration and arrangement of components described in the embodiments of the present invention or shown in the drawings. The invention may be implemented in different embodiments and carried out in various ways. Additionally, the expressions and predicates used in the embodiments regarding terms such as order, direction, etc. of devices or elements are merely used to simplify the description of the invention and indicate that the related devices or elements should simply have a particular order and orientation. It doesn't mean that. For example, terms such as “first” and “second” are used in the examples and claims to describe the present invention, but these terms are not intended to indicate or imply relative importance or intent.

In addition, terms or words used in this specification and claims should not be construed as limited to their common or dictionary meanings, and the inventor must comply with the technical idea of the present invention in order to explain the terms and concepts of the invention in the best possible way. It should be interpreted as written based on the meaning and concept.

Therefore, the present invention is not limited to the presented embodiments, and is within the equivalent scope of the technical idea of the present invention and the technical idea described in the patent claims below, as can be understood by those skilled in the art to which the present invention pertains. Various modifications and changes are possible.

The present invention can be more easily and clearly understood from the detailed description of the embodiments described together with the drawings.

In the following, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 3 shows the state of the process of manufacturing and forming the primary molding (M1), the secondary molding (M2), the tertiary molding (M3), and the pipe nut (PN) from the raw material (M0) according to the present invention.

Referring to FIG. 3, the molded products in each process of molding and manufacturing the integrated pipe nut (PN) for the electric vehicle battery platform of the present invention have the following molding structure.

The raw material M0 becomes cylindrical with a certain height, and a hollow blank 40 is formed in the central part of the axial direction.

That is, in the primary molding (M1), a thick cylindrical portion (41) and an extrusion molding portion (42) are formed from the raw material (M1).

The secondary molding (M2) has an upper extension portion 43 and a flange portion 44 formed on the upper portion of the thick cylindrical portion 41 from the primary molding M1, and an extrusion molding portion below the thick cylindrical portion 41. (42) A lower extension portion 45 is formed below the internal blank 40.

The tertiary molding (M3) is obtained by removing the scrap 46 that may be formed during extrusion forging of the flange portion 44 of the secondary molding (M2).

And, the nut portion of the pipe nut (PN), which becomes the final product by a tapping operation subsequently performed on the lower extension portion 45 of the secondary molding (M2) or the tertiary molding (M3) ( 47) is formed.

Here, according to the intended embodiment of the present invention, the pipe nut is formed by a tapping operation performed in a state in which the lower extension portion 45 is not formed in the secondary molding (M2) or the tertiary molding (M3). A nut portion 47 of (PN) may be formed.

The above molded products are molded using a separately provided mold device.

That is, the first molded product (M1) is formed by the first extrusion forging mold (10).

In addition, the secondary molding (M2) is formed by a second extrusion forging mold (20) prepared separately from the first extrusion forging mold (10).

In addition, the third molding (M3) is formed using a trimming mold (30) prepared separately from the second extrusion forging mold (20).

The integrated pipe nut (PN) for the electric vehicle battery platform through the above moldings, that is, the first molding (M1), the second molding (M2), and the third molding (M3), is made from the raw material (M0). A thick cylindrical portion 41 for forming the flange portion 44 by forward extruding the lower portion, excluding a certain section at the top of the material M0, and an extrusion molding portion 42 for forming the nut portion 47. A primary extrusion molding (M1) is formed, and an upper expansion portion (43) extending from the primary extrusion molding (M1) is formed at the upper center of the thick cylindrical portion (41). ) A flange portion 44 is formed from the upper outer peripheral surface of the extrusion molding portion 42, and a lower extension portion 45 for tapping is formed from the lower portion of the extrusion molding portion 42 to form a secondary forging molding (M2). , As an optional follow-up process, it is manufactured by forming a tertiary forging product (M3) through a trimming process to remove scrap 46 generated during forming the flange portion 44 from the secondary forging product (M2). .

A specific method of manufacturing the integrated pipe nut (PN) for the electric vehicle battery platform of the present invention using the above moldings will be described as follows.

Figure 4 shows a process flow chart showing the process of manufacturing the pipe nut (PN) of the present invention.

Referring to FIG. 4, the manufacturing method of the pipe nut (PN) in which the flange portion 44 and the nut portion 47 are formed integrally is to form a blank that is cylindrical and hollow in the axial direction, or is hollow in the axial direction. A step (S100) of preparing any raw material (M0) from which a hollow blank has not been formed;

Using the first extrusion forging mold 10 equipped with a primary extrusion forging die () and a primary extrusion forging punch (), the lower part of the raw material (M0) is extruded, excluding a certain upper section. A thick cylindrical portion 41 for forming the flange portion 44, and an extrusion molding portion 42 extending from the thick cylindrical portion 41 to form a step with a reduced cross-section to form the nut portion 47. ) an extrusion forging molding step (S200) of the first molded product (M1);

Using the second extrusion forging mold 20 equipped with a secondary extrusion forging die () and a secondary extrusion forging punch (), a blank in the upper center of the thick cylindrical portion 41 is formed from the primary molding (M1). While forming the upper extension portion 43 from which (40) is expanded, a flange portion 44 is formed from the upper outer peripheral surface of the thick cylindrical portion 43, and a nut portion is formed from the lower portion of the blank 40 of the extrusion molding portion 42. An electric vehicle in which the flange portion 44 and the nut portion 47 are formed integrally through the extrusion forging molding step (S300) of the secondary molding (M2) for forming the lower extension portion 45 to form (47). An integrated pipe nut (PN) for the battery platform will be manufactured.

In addition, according to the intended embodiment, after the extrusion forging forming step (S300) of the secondary molding (M2), a trimming step (400) is further performed on the secondary molding (M2) as the tertiary molding (M3). can do.

The trimming step (S400) is a process for removing scrap 46 that may be formed during molding of the flange portion 44, and includes a trimming die () into which a secondary molded product (M2) is input;

It is performed by a trimming punch () that removes the scrap 46 by pressing the boundary between the flange portion 44 of the input secondary molding (M2) and the scrap 46.

The embodiment referring to FIG. 4 describes the raw material M0 from which the hollow blank 40 is formed.

This embodiment describes an embodiment in which the first extrusion forging mold 10 is provided with a forward extrusion means based on the technical idea of the present invention. Therefore, the embodiment of the present invention can be implemented even on a material in which the blank 40 is not formed on the raw material M0.

This embodiment can be achieved by a first extrusion forging mold provided with a rear extrusion means, and the first extrusion forging mold provided with a rear extrusion means is a method known in the art from the embodiment provided with a front extrusion means. Since it can be carried out easily by anyone, the detailed explanation will be omitted.

In addition, the pipe nut (PN) of the present invention in which the flange portion 44 and the nut portion 47 are integrated can selectively undergo softening heat treatment, lubricating film, and hardening heat treatment during the molding process of each molded product.

In this way, the softening heat treatment, lubricating film, and hardening heat treatment processes can be selectively performed at each stage in consideration of the mechanical and physical properties of the pipe nut (PN) made of aluminum alloy.

Explaining this with reference to FIG. 4, the necessity of softening heat treatment is reviewed for the raw material (M0) prepared according to the step (b100) of preparing the raw material (M0), and if softening heat treatment is necessary, the softening heat treatment is performed. The first molded product extrusion forging step (B200) is entered, and if softening train is not needed, the first molded product extrusion forging step (B200) is entered.

At this time, whether a lubricating film process is necessary is simultaneously reviewed. If a lubricating film is necessary, the lubricating film process is performed and then the first molded product extrusion forging step (B200) is entered. If softening heat treatment is not required, the first molded product extrusion forging step is immediately performed. Enter at (ㄴ200).

In addition, the necessity of softening heat treatment is reviewed for the molded primary molding (M1), and if softening heat treatment is necessary, the softening heat treatment is performed and then the secondary molding extrusion forging step (B300) is entered. If softening heat treatment is not necessary, It immediately enters the second molded product extrusion forging stage (B200).

At this time, whether a lubricating film process is necessary is simultaneously reviewed. If a lubricating film is necessary, the lubricating film process is performed and then the secondary molding extrusion forging step (B300) is entered. If softening heat treatment is not required, the secondary molding extrusion forging step is immediately performed. Enter at (ㄴ300).

In addition, for the molded secondary molding (M1), the necessity of hardening heat treatment is reviewed, and if hardening heat treatment is necessary, the hardening heat treatment is performed and then the trimming step (B400) is entered. If the hardening heat treatment is not necessary, the trimming step ( Enter at ㄴ400).

The hardening heat treatment process is performed on the secondary molding (M2) before the step of forming the third molding, and the secondary molding (M2) is maintained at 530 ° C. for 2 hours and then rapidly cooled with water and then cooled at 180 ° C. for 6 hours. By maintaining and then cooling, the metal structure becomes hard and mechanical and physical performance is improved. At this time, the Brinell hardness is preferably 30 to 35 HB.

Since this type of hardening heat treatment is performed at a relatively high temperature to change the metal structure densely, thermal deformation inevitably occurs in the final molded product when the curing heat treatment is performed on the final molded product that has been manufactured. Therefore, in the present invention, a hardening heat treatment is performed on the secondary molding (M2) before the step of molding the tertiary molding, which becomes the final molding, and then a process of manufacturing the tertiary molding (M3) is performed by trimming, thereby producing the final molding. It is possible to minimize deformation due to heat in the third molded product (M3) that becomes the molded product. The hardening heat treatment is preferably performed to achieve a Rockwell hardness of 85 to 95 HRF.

Also, preferably, the hardening heat treatment is performed on the entire surface forming the upper extension 43 and the lower extension 45 of the secondary molding M2.

In the softening heat treatment process, the temperature of the furnace containing the raw material (M0) or the primary molded product (M1) is maintained at 500°C for 4 hours, and the temperature of the furnace is maintained at 200°C. The raw material (M0) or primary molded product (M1) is furnace-cooled for 15 to 25 hours, and the furnace-cooled raw material (M0) or primary molded product (M1) is cooled to 200°C or lower. ) is carried out through a sequential process of taking it out of the container and cooling it in the air.

To form the lubricating film, the material coated with the phosphate film or zinc phosphate film is immersed in a soap-based lubricating liquid to react with the film and generate zinc stearate, a metallic soap, in the middle layer.

This softening heat treatment softens the metal structure of the raw material (M0) or the first molded product (M1), allowing the subsequent extrusion forging process to proceed smoothly.

In addition, by forming a lubricating film on the metal surface of the raw material (M0) or the first molded product (M1), the subsequent extrusion forging process and tapping work are performed smoothly.

Then, the extrusion molding portion 32 or the lower extension portion () is formed on the secondary molding (M2) in which the flange portion 44 and the extrusion molding portion 42 are formed, or the tertiary molding (M3) in which the trimming is completed. By tapping to form the nut portion 47 made of female threads, the flange portion 44 and the nut portion 47 are formed as one piece, completing the manufacturing of the pipe nut (PN) to be mounted on the battery platform of the electric vehicle. do.

In the following, an apparatus in which the method of manufacturing the integrated pipe nut (PN) for the electric vehicle battery platform is performed will be described.

In the first forging mold 10, a primary forging molding (M1) is manufactured from a blank material (M0), and in the second forging mold 20, a secondary forging molding (M2) is manufactured from the primary forging molding (M1). And, in the trimming mold 30, a tertiary forging molding (M3) is manufactured from the secondary forging molding (M2).

Figure 5 shows a cross-sectional view of the first extrusion forging mold of the present invention.

Referring to FIG. 5, the first extrusion forging mold 10 includes a first lower plate 100, a first upper plate 110, a first movable plate 120, a first extrusion forging die 130, 1 It consists of a primary extrusion forging punch fixture 140 and a primary extrusion forging punch 150.

The first lower plate 100 has a primary extrusion forging die 130 installed in the upper center, and four first guide posts 101 stand vertically in all directions around the primary extrusion forging die 130. do.

A first movable plate 120 is horizontally coupled to the upper part of the first guide post 101 so as to be movable up and down. The first movable plate 120 has a first guide bush 121 formed on the surface in contact with the first guide post 101 to help the first movable plate 120 move up and down smoothly.

The first upper plate 110 has a first shank 111 located in the center, and a primary extrusion forging punch fixture 140 is fixed to the lower part thereof.

The first movable plate 120 has a primary extrusion forging punch fixture 140 fixed between the first lower plate 100 and the first upper plate 110, and is connected to the first lower plate 100 and the first upper plate 110. 1 It is supported on the first guide post 101 between the upper plates 110 and is installed to be able to move up and down.

The primary extrusion forging die 130 is a primary molded product including a receiving part 131 into which the raw material (M0) is input, a thick cylindrical part 41 and an extrusion molding part 42 from the raw material (M0). It is formed as a primary molding part 132 for molding (M1), and is wrapped in a first container 135 installed on the first die plate 134 within the first die housing 133 to form a first lower plate. (100) It is fixed in the upper center.

The receiving portion 131 is located at the upper center of the lower plate 100 and the raw material M0 is input.

The primary molding portion 132 is formed as a space that narrows while extending downward of the receiving portion 131, and is formed by forming a thick cylindrical portion 41 and an extrusion molding portion 42 from the raw material M0 pushed in by pressing force. The first molding (M1) provided with is formed.

A first punch holder 141 is fixed to the primary extrusion forging punch fixing table 140, and a first punch block 142 is fixed to this first punch holder 141. Additionally, the primary extrusion forging punch 150 is fixed to the first punch block 142.

The primary extrusion forging punch 150 consists of an upper center punch 151 and a first upper pressure punch 152.

The upper center punch 151 extends vertically downward from the lower center of the first punch holder 141 to form a blank 40 of the raw material (M0) introduced into the receiving portion 131 of the primary extrusion forging die 130. ) is inserted into.

The first upper pressure punch 152 is formed to extend cylindrically from the lower part of the first punch holder 141 to surround the outside of the upper center punch 151 to form a receiving portion of the primary extrusion forging die 130 ( 131), the upper part of the raw material (M0) inputted is pressed to form the first molded product (M1) including the thick cylindrical part (41) and the extrusion molding part (42).

Meanwhile, an ejecting tool 160 is formed below the first extrusion forging die 130.

The ejecting tool 160 is supported on the first die plate 134 and ejects the completed primary molding (M1) from the primary extrusion forging die 130.

The first extrusion forging mold 10 configured in this way is configured to inject the raw material M0 into the first extrusion forging die 130 in a state where the first extrusion forging punch 150 is spaced apart from the upper part of the first extrusion forging die 130. ) into the receiving part 131, and then operating the primary extrusion forging punch 150, the primary extrusion forging is performed together with the first movable plate 120 that is guided to the first guide post 101 and moves up and down. The punch fixture 140 descends and approaches the primary extrusion forging die 130.

At this time, the upper center punch 151 of the first extrusion forging punch 150 is inserted into the upper part of the blank 40 in the center of the raw material M0, and the first upper pressure punch 152 is fixed to the raw material M0. ) applies pressure to the upper end of the raw material (M0), the raw material (M0) is pushed from the receiving portion (131) into the primary molding portion (132), forming the thick cylindrical portion (41) and the extrusion molding portion (42). The branch is formed into the first molded product (M1).

The primary molded product (M1) formed in this way is demolded from the primary extrusion forging die 130 by the eject tool 160 and formed into a secondary molded product (M2) through the second extrusion forging mold 20.

Figure 6 shows a cross-sectional view of the second extrusion forging mold of the present invention.

Referring to FIG. 6, the second extrusion forging mold 20 includes a second lower plate 200, a second upper plate 210, a second movable plate 220, a secondary extrusion forging die 230, and 2. It consists of a secondary extrusion forging punch fixture (240) and a secondary extrusion forging punch (250).

The second lower plate 200 has a secondary extrusion forging die 230 installed in the upper center, and four second guide posts 201 are installed vertically in all directions around the secondary extrusion forging die 230. do.

A first movable plate 220 is horizontally coupled to the upper part of the second guide post 201 so as to be movable up and down. The first movable plate 220 has a second guide bush 221 formed on the surface in contact with the second guide post 201 to help the second movable plate 220 move up and down smoothly.

The second upper plate 210 has a second shank 211 located in the center, and a primary extrusion forging punch fixture 240 is fixed to the lower part thereof.

The second movable plate 220 also has a primary extrusion forging punch fixture 240 fixed to the second upper plate 210 between the second lower plate 200 and the second upper plate 210. , is supported on the second guide post 201 between the first lower plate 200 and the first upper plate 210 and is installed to be movable up and down.

The secondary extrusion forging die 230 is formed of a secondary molding part 231 and a two-stage step part 232, into which the primary molding material (M1) is input, and the first molding material (M1) is formed within the second die housing 233. It is wrapped around the first container 235 installed on the die plate 234 and fixed to the upper center of the second lower plate 200.

The secondary molding part 231 is formed in a narrower space than the step part 232 of the second stage, and the extrusion molding part 42 of the injected primary molding product M1 is located there.

The step portion 232 of the second stage is formed in a space wider than the secondary molding portion 231 and the thick cylindrical portion 41 of the input primary molding product (M1) is located therein. From this, it is possible to mold the secondary molding (M2) in which the upper extension portion 43 and the flange portion 44 are formed.

A second punch holder 241 is fixed to the secondary extrusion forging punch fixture 240, and a second upper pressure punch 251 of the secondary extrusion forging punch 250 is fixed to the second punch holder 241. do.

The secondary extrusion forging punch 250 consists of a second upper pressure punch 251 and a lower center punch 252.

The second upper pressurizing punch 251 has a lower end formed in a shape capable of forming the upper extension 43 and the flange 44 of the secondary molding M2 and is fixed to the lower part of the second upper plate 210. It is also fixed to the second movable plate 220 and can move up and down while being supported by the second guide post 201, and when it descends, the lower part is inserted into the second container 235 and the second extrusion forging die 230 ) is applied to the upper part of the secondary molded product (M2) by applying pressure to allow the secondary molded product (M2) having the upper extension portion 43 and the flange portion 44 to be molded.

The lower center punch 252 is installed inside the sleeve 236 supported by the second die plate 234 on the second lower plate 200, and the primary molding (M1) inputted into the secondary extrusion forging die 230. ) is located at the upper center of the second lower plate 200 from below and is inserted into the blank 40 inside the extrusion molding portion 42 of the primary molding (M1) inputted into the secondary extrusion forging die 230. and the lower extension portion 45 of the secondary molding (M2) is molded.

The sleeve 236 supports the lower end of the primary molding (M1) inputted into the secondary extrusion forging die 230 so that the second upper pressure punch 251 forms the secondary molding (M2). When pressing (M1), the upper extension portion 43 and the flange portion 44 provide a reaction force that can be formed smoothly.

In addition, the sleeve 236 is such that when the first upper pressure punch 251, which formed the secondary molded product (M2), is spaced apart from the secondary extrusion forging die 230, the lower center punch 252 forms the secondary molded product (M2). ) Supports the lower center punch (252) so that it can be demolded.

The second extrusion forging mold 20 configured in this way is configured such that the first molding M1 is pressed into the secondary extrusion forging die (M1) with the second upper pressure punch 250 spaced apart from the upper part of the secondary extrusion forging die 230. When input into 230), the lower end of the input first molded product (M1) is supported by the sleeve 236.

In this state, when the secondary extrusion forging punch 250 is operated, the secondary extrusion forging punch fixture 240 descends together with the second movable plate 220 that is guided by the second guide post 201 and moves up and down. It approaches the secondary extrusion forging die 230.

At this time, the lower center punch 252 of the secondary extrusion forging punch 250 is inserted into the lower part of the blank 40 in the center of the input primary molding (M1) and supports the primary molding (M1) while supporting the primary molding (M1). A lower expansion portion 45 is formed, and the second upper pressure punch 252 pressurizes and strikes the upper part of the input primary molding (M1) to form a secondary molding having an upper expansion portion 43 and a flange 44. (M2) can be formed.

The secondary molding (M2) formed in this way is formed when the second upper pressure punch 251 is spaced apart from the secondary extrusion forging die 230, and the lower center punch 232 is formed in the secondary extrusion forging die 230. The car molding (M2) is demolded.

In the secondary molding (M2) demolded from the second extrusion forging mold 20, scrap 46 may be formed around the flange portion 44 during the process of forming the flange portion 44. This scrap 46 ) can be removed from the trimming mold 30.

Figure 7 shows a trimming mold of the present invention.

Referring to FIG. 7, the trimming mold 30 includes a third lower plate 300, a third upper plate 310, a third movable plate 320, a trimming die 330, a trimming punch fixture 340, and It consists of a trimming punch (350).

The third lower plate 300 has a trimming die 330 installed in the upper center, and four third guide posts 301 are installed vertically in all directions around the trimming die 330.

A third movable plate 320 is horizontally coupled to the upper part of the third guide post 301 so as to be movable up and down. The third movable plate 320 has a third guide bush 321 formed on the surface in contact with the third guide post 301 to help the third movable plate 320 move up and down smoothly.

A third shank 311 is located in the center of the third upper plate 310, and a trimming punch holder 340 is fixed to its lower portion.

The third movable plate 320 is attached to the third guide post 301 between the third lower plate 300 and the third upper plate 310 so that the trimming punch 350 can perform a trimming punch ( The third punch holder 341 that fixes 350) is fixed and positioned to be lifted up and down.

The trimming die 340 is formed in a shape corresponding to the shape of the secondary molding M2 and is fixed to the upper part of the third lower plate 300.

The trimming punch 350 is fixed to the lower part of the third upper plate 310 and the third movable plate 320, and the stripper 351 is formed to form the flange portion 44 and the scrap 46 of the injected secondary molding (M2). ) to remove the scrap 46 by pressing the border.

The dimensional tolerance of the pipe nut (PN) by the cold forging method and device of the present invention is ±0.5mm at 3.0~6.0mm, ±1.5mm at 6.0~30mm, ±2mm at 30~120mm, and ±2mm at 120~315mm. It is performed at approximately ±3mm, improves the mechanical and physical properties of aluminum materials, and satisfies high-quality forming precision.

So far, the present invention has been examined with a focus on preferred embodiments.

The specification of the present invention has been described with a focus on preferred embodiments with reference to the accompanying drawings, but the described embodiments and the configuration shown in the drawings are related to one of the most preferred embodiments of the present invention and do not represent the entire technical idea. Therefore, those skilled in the art should understand that there may be various equivalents and modifications that can be substituted for them without departing from the scope of the present invention.

Therefore, the scope of the present invention is not limited to the presented embodiments, but should be interpreted by the described claims to include many modifications, and the scope of the present invention should be interpreted by those skilled in the art to which the present invention pertains. Since there may be various modifications and changes possible within the equivalent scope of the technical idea described in the technical idea and the patent claims described below, the scope of the present invention is the scope of the patent claims described to include many such modifications. It must be interpreted by .

10: first extrusion forging mold 100: first lower plate
101: first guide post 111: first shank
110: first upper plate 121: first guide bush
120: first movable plate 130: first extrusion forging die
131: storage unit 132: primary molding unit
133: first die housing 134: first die plate
135: first container 140: first compression forging punch fixture
141: first punch holder 142: first punch block
150: Primary extrusion forging punch 151: Upper center punch
152: First upper pressure punch 160: Eject tool
20: second extrusion forging mold 200: second lower plate
201: second guide post 211: first shank
210: first upper plate 221: second guide bush
220: first movable plate 230: secondary extrusion forging die
231: secondary forming part 232: step part
233: second die housing 234: second die plate
235: second container 236: sleeve
240: 1st compression forging punch fixture 241: 2nd punch holder
250: Second extrusion forging punch 251: Second upper pressure punch
252: Lower center punch
30: trimming mold 300: third lower plate
301: Third guide post 311: Third shank
310: first upper plate 321: second guide bush
320: first movable plate 330: trimming die
340: Trimming punch holder 341: Third punch holder
350: Trimming punch 351: Stripper
40: Blank 41: Rear cylindrical portion
42: extrusion molding part 43: upper expansion part
44: Flange portion 45: Lower extension portion
46: Scrap 47: Threaded portion
M0: Raw material M1: Primary molding
M2: Secondary molding M3: Trimming molding
PN: pipe nut

Claims (9)

In manufacturing a pipe nut (PN) for an electric vehicle battery platform consisting of a flange portion 44 mounted on the battery platform and a nut portion 47 to which a bolt is fastened,
A method of manufacturing an integrated pipe nut for an electric vehicle battery platform, characterized in that the flange portion and the nut portion are manufactured by forging and molding integrally.
In claim 1,
A step (S100) of preparing a raw material (M0) that has a cylindrical shape and is formed with a blank 40 that is hollow in the axial direction, or in which a blank that is hollow in the axial direction is not formed;
Using the first extrusion forging mold 10 equipped with the primary extrusion forging die 130 and the primary extrusion forging punch 150, except for a certain upper section of the raw material M0, the lower part thereof A thick cylindrical portion 41 for forming the flange portion 44 by extrusion, and an extrusion molding portion extending from the thick cylindrical portion 41 to form a step with a reduced cross-section in order to mold the nut portion 47. A first molding (M1) extrusion forging forming step (S200) of forming (42);
Using the second extrusion forging mold 20 provided with the secondary extrusion forging die 230 and the secondary extrusion forging punch 250, the upper center of the thick cylindrical portion 41 is formed from the primary molding M1. A flange portion 44 is formed from the upper outer circumferential surface of the thick cylindrical portion 41 while forming an upper extension portion 43 through which the blank 40 is expanded, and a flange portion 44 is formed from the lower portion of the blank 40 of the extrusion molding portion 42. Including the extrusion forging forming step (S300) of the secondary molding (M2) of forming the lower extension portion 45 to form the nut portion 46, the flange portion 44 and the nut portion 47 are formed integrally. A method of manufacturing an integrated pipe nut for an electric vehicle battery platform, characterized in that.
In claim 2,
In the step (b200) of extrusion forging the primary molding (M1),
When the raw material (M0) has a hollow blank 40 in the axial direction, the extrusion molding portion 42 is forged by forward extrusion,
A method of manufacturing an integrated pipe nut for an electric vehicle battery platform, characterized in that when the raw material (M0) does not have a blank 40 that is hollow in the axial direction, the extrusion molding portion 42 is forged by rear extrusion.
In claim 2,
After the second molded product (M2) forging forming step (S300),
An integrated type for an electric vehicle battery platform, further comprising performing a trimming process (S400) to remove scrap 46 generated during molding of the flange portion 44 from the secondary molding (M2). Manufacturing method of pipe nuts.
In claim 2,
selectively performing softening heat treatment on the raw material (M0) and the first molded product (M1);
A step of treating the softening heat treated raw material (M0) or molded product (M1) with a lubricating film;
A method of manufacturing an integrated pipe nut for an electric vehicle battery platform, optionally further comprising the step of hardness-enhancing heat treatment before trimming the secondary molding (M2).
In claim 2,
The first extrusion forging mold 10 is,
A primary extrusion forging die 130 and a first guide post 101 are fixed to the upper part of the first lower plate 100,
The primary extrusion forging punch 150 is fixed to the lower part of the first upper plate 110,
A first punch holder 141 on which the primary extrusion forging punch 150 is fixed is fixed between the first lower plate 100 and the first upper plate 110 and is fixed at the upper part of the first guide post 101. It includes a first movable plate 120 positioned to be lifted up and down toward the primary extrusion forging die 130,

The first extrusion forging punch 150,
an upper center punch 151 extending vertically downward from the lower center of the first punch holder 141 and inserted into the blank 40 of the raw material M0;
It is formed to extend cylindrically from the lower part of the first punch holder 141, surrounding the outside of the upper center punch 151, and presses the upper part of the raw material (M0) inputted into the first extrusion forging die 130 to form a cylindrical shape. It includes a first upper pressure punch (152) for forming a primary molding (M1) having a cylinder portion (41) and an extrusion molding portion (42),

An integrated pipe for an electric vehicle battery platform, characterized in that the ejecting tool 160 formed below the first extrusion forging die 130 ejects the first molded product (M1) from the first extrusion forging die 130. Nut forging method.
In claim 2,
The second extrusion forging mold 20,
A secondary extrusion forging die 230 and a second guide post 201 are fixed to the upper part of the second lower plate 200,
A secondary extrusion forging punch 250 is fixed to the lower part of the second upper plate 210,

A second punch holder 241 is fixed between the second lower plate 200 and the second upper plate 210, and a second movable plate 220 is positioned to be lifted up and down on the second guide post 201. Includes,

The secondary extrusion forging die 230,
It is located at the upper center of the second lower plate 200 and forms a space into which the first molded product (M1) is input,
A secondary molding (M2) having an upper extension 43, a flange portion 44, and a lower expansion portion 45 is formed from the input primary molding (M1),

The secondary extrusion forging punch 250,
A second upper pressure punch 251 extending vertically downward from the lower center of the second punch holder 241 to form an upper expansion portion 43 and a flange portion 44 formed in the primary molding (M1). and,
The upper center of the second lower plate 200 is inserted into the internal blank 40 of the extrusion molding portion 42 of the primary molding product M1 inputted into the secondary extrusion forging die 230 to form a lower extension portion 45. It includes a lower center punch 252 that allows it to be formed,

After the secondary molding (M2) is formed, as the upper second upper pressure punch 251 rises, the lower center punch 252 rises to eject the molded secondary molding (M2). A method for forging an integral pipe nut for an electric vehicle battery platform, comprising:
A device for manufacturing a pipe nut (PN) for an electric vehicle battery platform consisting of a flange portion 44 mounted on the battery platform and a nut portion 47 to which a bolt is fastened,
A first extrusion forging mold (10) for forming a primary molding (M1) having a thick cylindrical portion (41) and an extrusion molding portion (42) from the raw material (M0);
Including a second extrusion forging mold 20 that forms a secondary molding (M2) having an upper extension 43, a flange portion 44, and a lower extension 45 from the primary molding (M1). It comes true,

The first extrusion forging mold 10 is,
A primary extrusion forging die 130 formed on the first lower plate 100;
A primary extrusion forging punch 150 fixed to the lower part of the first upper plate 110;
It consists of a first movable plate (120) on which the first punch holder (01) is fixed to the first guide post (120) between the first lower plate (100) and the first upper plate (110) and can be raised and lowered. Lose,

The first extrusion forging die 130,
A storage portion 131 located at the upper center of the lower plate 100 into which the raw material M0 is input;
A primary molding (M1) having a thick cylindrical portion (41) and an extrusion molding portion (42) is formed from the raw material (M0), which is formed as a space extending downward of the receiving portion (131) and is pushed in by pressing force. It includes a primary forming part 132 that does,

The first extrusion forging punch 150,
an upper center punch 151 extending vertically downward from the lower center of the first punch holder 141 and inserted into an axially hollow blank 40 formed in the raw material M0;
It is formed to extend cylindrically from the lower part of the first punch holder 141, surrounding the outside of the upper center punch 151, and presses the upper part of the raw material (M0) inputted into the first extrusion forging die 130 to form a cylindrical shape. a first upper pressure punch (152) for forming a primary molding (M1) having a cylinder portion (41) and an extrusion molding portion (42);
It includes an ejecting tool 160 for ejecting the primary molded product (M1) from the primary extrusion forging die 130,

The second extrusion forging mold 20,
A secondary extrusion forging die 230 formed on the second lower plate 200;
a secondary extrusion forging punch 250 fixed to the lower part of the second upper plate 210;
It consists of a second movable plate 220 on which the second punch holder 241 is fixed to the second guide post 201 between the second lower plate 200 and the second upper plate 210 and is positioned to be raised and lowered. Lose,

The secondary extrusion forging die 230,
It is located at the upper center of the second lower plate 200, and the primary molding product (M1) is input. It is inserted into the blank 40 from the lower part of the blank 40 of the input primary molding material (M1) and has a lower extension portion 45. ) and a secondary molding part 231 forming a;
It includes a two-stage step portion 232 forming an upper extension portion 43 and a flange portion 44,

The secondary extrusion forging punch 250,
A second punch holder () extends vertically downward from the lower center of the second punch holder () to form an upper extension portion 43 and a flange portion 44 on the primary molding (M1) inputted into the secondary extrusion forging die (230). 2 upper pressure punch (251);
It is inserted into the blank 40 inside the extrusion molding part 42 of the primary molding (M1) inputted into the secondary extrusion forging die 230 at the upper center of the second lower plate 200 to form a lower extension part 45. ) includes a lower center punch (252) for forming,

After the secondary molding (M2) is molded, the lower center punch 252 rises as the upper second upper pressure punch 251 rises, making it possible to eject the molded secondary molding (M2). Manufacturing device for integrated pipe nuts for electric vehicle battery platforms.
In claim 8,
The device for manufacturing the pipe nut (PN) for the electric vehicle battery platform,
It further includes a trimming mold 30 from the second extrusion forging mold 20 to remove scrap 46 formed on the flange portion 44 of the secondary molding M2,
The trimming mold 30 is,
A trimming die 330 formed on the third lower plate 300 and into which the secondary molding (M2) is input;
a trimming punch 350 that is fixed to the lower part of the third upper plate 310 and removes the scrap 46 by pressing the boundary between the flange portion 44 of the injected secondary molding product M2 and the scrap 46;
A third punch holder 341 for fixing the trimming punch 350 is fixed between the third lower plate 300 and the third upper plate 310 so that the trimming punch 350 can perform the trimming operation. A manufacturing device for an integrated pipe nut for an electric vehicle battery platform, comprising a third movable plate (320) that can be raised and lowered on the guide post (301).

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