CN113560439B - Processing method of door cover edge rolling - Google Patents

Processing method of door cover edge rolling Download PDF

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Publication number
CN113560439B
CN113560439B CN202110795579.5A CN202110795579A CN113560439B CN 113560439 B CN113560439 B CN 113560439B CN 202110795579 A CN202110795579 A CN 202110795579A CN 113560439 B CN113560439 B CN 113560439B
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China
Prior art keywords
rolling
binding
edge
door cover
fillet
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CN113560439A (en
Inventor
江克洪
谢陈阳
董双龙
张超
吴丁磊
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Geely Automobile Group Co ltd
Zhejiang Geely Holding Group Co Ltd
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Geely Automobile Group Co ltd
Zhejiang Geely Holding Group Co Ltd
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Priority to CN202110795579.5A priority Critical patent/CN113560439B/en
Publication of CN113560439A publication Critical patent/CN113560439A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D39/00Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
    • B21D39/02Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of sheet metal by folding, e.g. connecting edges of a sheet to form a cylinder
    • B21D39/021Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of sheet metal by folding, e.g. connecting edges of a sheet to form a cylinder for panels, e.g. vehicle doors
    • B21D39/023Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of sheet metal by folding, e.g. connecting edges of a sheet to form a cylinder for panels, e.g. vehicle doors using rollers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D37/00Tools as parts of machines covered by this subclass
    • B21D37/16Heating or cooling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00Making other particular articles
    • B21D53/88Making other particular articles other parts for vehicles, e.g. cowlings, mudguards
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/25Process efficiency

Abstract

The invention provides a processing method of door cover border, belonging to the technical field of border processing. It has solved the problem that there are fracture and distortion in the door closure border fillet after the current shaping. The processing method of the door cover edge rolling comprises the following steps: A. coating, gluing and splicing; B. carrying out first rolling forming; C. heating; D. and (5) rolling and forming for the second time. The processing method for the door cover edge rolling has the advantages that the problem that the existing door cover edge rolling is easy to crack and distort after being formed is solved while the radius of the edge rolling fillet is ensured to be smaller.

Description

Processing method of door cover edge rolling
Technical Field
The invention belongs to the technical field of edge knurling, and relates to a door cover edge knurling method.
Background
The door cover comprises an inner plate assembly and an outer plate made of metal, and the existing binding process is a forming technology of rolling the edge of the outer plate according to a preset track by a robot with a binding tool.
If the single rolling angle of the edge of the outer plate is too large, the edge rolling is easy to generate flash, so the existing edge rolling process can divide the edge rolling times according to the angle of the edge of the outer plate after the outer plate is subjected to punch forming, namely the outer edge is rolled for many times in the step of roll forming so that the outer edge forms the edge rolling.
Further, the border has an inner fillet radius R and an outer fillet radius R, the outer plate has a thickness t, the bending radius a = R/t, the bending radius of the outer plate is limited by the material of the outer plate, if the bending metal plate is too small, the border fillet will crack due to too large deformation, so that the size of the inner fillet radius R is limited on the premise that the thickness t of the outer plate is certain, and the existing outer fillet radius R cannot be made small; furthermore, stress is accumulated on the edge rolling fillet by multiple rolling, and the edge rolling fillet is cracked and distorted.
In view of the above, one of ordinary skill in the art can easily set the radius R of the external fillet to be larger and reduce the number of times of rolling, for example, chinese patent literature discloses a rolling process and a rolling device for an aluminum alloy door cover having a large angle of opening [ patent No.: 201811254866.X; application publication No.: CN109454140A ], step 1, feeding; step 2, pre-edge covering: the opening angle of the edge of the outer plate is smaller than 90 degrees; step 3, edge rolling: and (4) performing edge rolling on the whole edge of the outer plate by using an edge rolling tool on the edge rolling robot until the edge of the outer plate completely wraps the edge of the inner plate.
This patent adopts the mode of this kind of compound border of mixed border robot of mechanism of borduring to reduce the roll extrusion number of times to the outer panel board edge, and this kind of mode obviously is starting from the angle of avoiding the border fillet to produce the crackle defect and guarantees the quality of border to this kind of technology obviously does not consider the border fillet radius, leads to the border fillet radius after the border shaping to have great condition.
Disclosure of Invention
The invention aims to solve the problems in the prior art, and provides a processing method for door cover edge rolling, which ensures that the radius of a rounded corner of the edge rolling is smaller and solves the problem that the rounded corner of the edge rolling is easy to crack and distort after the edge rolling forming of the door cover.
The purpose of the invention can be realized by the following technical scheme: a processing method for the door cover border, the door cover includes the inner plate assembly and planking made of metal, characterized by that, the processing method includes the following steps:
A. coating, gluing and splicing: firstly coating edge folding glue on an outer plate or an inner plate assembly, and then arranging the outer plate on the outer side of the inner plate assembly to ensure that the outer plate is attached to the inner plate assembly and the edge of the outer plate extends out relative to the edge of the inner plate assembly;
B. first roll forming: rolling the edge of the outer plate to enable the edge of the outer plate to be turned over towards the inner side of the inner plate assembly until the edge of the outer plate forms a border wrapping the edge of the inner plate assembly, wherein the border comprises a fillet area with an inner fillet and an outer fillet;
C. heating: heating the rolled edge to 90-350 ℃;
D. and (3) rolling and forming for the second time: and rolling the outer fillet surface of the edge rolling until the fillet area of the edge rolling is reduced.
After the first rolling forming of the door cover edge rolling is finished, the edge rolling is pertinently heated to 90-350 ℃, and the plasticity of the edge rolling is improved through the technical steps. On this basis, carry out the roll forming for the second time to the outer fillet surface of piping for the fillet is regional to shrink under the exogenic action, and the fillet is regional to be dwindled promptly, and through the process step with step C and step D combination, the fracture and the distortion that the piping fillet produced in the roll forming process of the first time are got rid of to the at utmost, solve the problem that current door closure piping formation back easily takes place fracture and distortion when guaranteeing that piping fillet radius is less from this. Further, the local position of planking is heated again after the planking edge is rolled and formed, for the solidification reservation time of hem glue for the hem glue of scribbling in step A is solidified before the heating, avoids the hem glue inefficacy, guarantees the relative position relation between inner panel assembly and the planking, guarantees the stability of door closure size from this.
In the processing method for door cover edge rolling, in the step D, the outer corner surface is rolled on the outer side of the outer plate by the edge rolling tool, and then the outer corner surface is rolled on the inner side of the outer plate, the edge rolling tool is a rolling head having an axial lead, and when the outer corner surface is rolled, an included angle between the axial lead of the rolling head and the edge rolling plane is an acute angle. The position where the external fillet is most prone to cracking is the position with the largest bending degree, namely the external fillet surfaces on the inner side and the outer side of the outer plate, and the rolling head rolls the position where the surface of the external fillet needs to be rolled more accurately by arranging an acute included angle between the axial lead of the rolling head and the edge rolling plane and then rolling; during rolling, the rolling sequence is set consciously, namely the outer fillet surface is rolled on the outer side of the outer plate to enable the fillet area to shrink from the outer side of the outer plate to the inner side of the outer plate, then the outer fillet surface is rolled on the inner side of the outer plate, the rolling sequence is staggered, and the fillet area can extend towards the opening of the rolled edge by virtue of the structure that the rolled edge is arranged on the inner side of the inner plate assembly.
In the above door cover binding processing method, in step D, the binding tool rolls the external round surface along the binding length direction. This kind of rolling mode is convenient for the rolling head and is evenly acted on the surperficial at the fillet outside with rolling force for the regional whole of fillet reduces, reduces the probability that the local position of piping takes place the distortion.
In the above-described door cover knurling process, in step D, the knurling tool applies a rolling force to the external round corner surface on the outer side of the outer panel that is smaller than a rolling force to the external round corner surface on the inner side of the outer panel. The rolling force applied to the outer fillet surface on the outer side of the outer plate is reduced relative to the inner side of the outer plate, so that the fillet area is contracted from the outer side of the outer plate to the inner side of the outer plate as far as possible in the degree of ensuring that the binding plane is not distorted; and the rolling force applied to the external fillet surface on the inner side of the outer plate is increased relative to the outer side of the outer plate, so that the fillet area extends towards the opening of the binding as much as possible, thereby reducing the fillet area to the maximum extent and removing the cracks generated in the first rolling forming process of the binding fillet. Furthermore, the rolling mode of the zone force application avoids the possibility of the deformation of the edge rolling to the maximum extent.
In the processing method for the door cover edge rolling, in the step D, the rolling speed of the edge rolling tool is 50-250 mm/s, the rolling pressure is 1000-2500N, and after the second rolling forming, the radius R of the excircle corner of the edge rolling is less than or equal to 1.5mm. The rolling force range is given, so that different rolling forces applied to different positions of the surface of the external fillet can be selected from the range, the actual stress of the binding fillet is determined and uniform, and the possibility of distortion of the binding fillet caused by the change of the rolling force is reduced to the maximum extent; the excircle corner radius of the border of less than or equal to 1.5mm improves the finishing degree of the border of the door cover, and the invention aims to reduce the radius of the border fillet.
In the processing method for the door cover roller hemming, after the step D, the roller hemming is checked, and the whole shape of the roller hemming and the surface flatness of the roller hemming are debugged in time on site. The integrity of the roller edge after the secondary roller forming is ensured through the debugging of the roller edge, thereby ensuring the delivery quality of the roller edge of the door plate.
In the above-described door cover piping method, in step C, the piping of the outer panel is heated by the induction coil. Adopt induction coil to heat the border for the heating convenience of border improves, and induction coil heating is prior art, and it sets up the position and can confirm according to actual need, so can directly set up on the border fetal membrane through with current induction coil, makes the door closure need not to carry still to heat on the border fetal membrane after first roll forming, has improved the border heating convenience from this.
In the above-described door cover piping method, in step C, the piping of the outer panel is heated by the induction heating table. The induction heating table is heating equipment specially used for heating workpieces in the prior art, so that the heating mode can improve the heating temperature control of the outer plate edge rolling.
Compared with the prior art, the processing method of the door cover border provided by the invention has the following advantages:
1. the formed edge rolling is reprocessed, namely, the formed fillet area is reduced by heating and rolling again, and cracks at the external corner can be removed by rolling again, so that the problem that the existing door cover is easy to crack and distort after edge rolling is solved while the radius of the edge rolling fillet is smaller.
2. And the roller edge formed by the second rolling is debugged, so that the overall shape of the roller edge and the flatness of the outer surface of the roller edge are well adjusted in the delivery stage of the door cover, and the quality of the door cover is ensured.
Drawings
FIG. 1 is a flow chart of the present door cover binding process.
FIG. 2 is a schematic view of door trim after step A.
Fig. 3 is a schematic view of the rolling state in step B.
Fig. 4 is a partially enlarged view a of fig. 3.
Fig. 5 is a first schematic view of the rolling state in step D.
Fig. 6 is a schematic view of the rolling state in step D.
Fig. 7 is a partially enlarged view B of fig. 6.
In the figure, 1, an inner plate assembly; 2. an outer plate; 3. folding glue; 4. trimming; 41. a fillet area; 411. a fillet; 412. a bullnose; 5. and (6) rolling a head.
Detailed Description
The following are specific embodiments of the present invention and are further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.
As shown in FIG. 1, the processing method for the edge rolling of the door cover comprises an inner plate assembly 1 and an outer plate 2 made of metal, wherein the outer plate 2 is made of aluminum alloy in the embodiment, and the processing steps of the edge rolling 4 can be divided into four steps: A. coating, gluing and splicing; B. carrying out first rolling forming; C. heating; D. and (5) rolling and forming for the second time.
Before explaining the four processing steps, it is clear that: the outer side and the inner side referred to in the present invention are based on the inner side and the outer side of the door cover; the binding tool is a machining tool which is available in the prior art and acts on the surface of a workpiece, and the specification and the type of the binding tool can be selected according to actual machining requirements.
As shown in fig. 2, in step a, in this embodiment, the outer plate 2 is coated with the hemming adhesive 3, in actual production, the inner plate assembly 1 may also be coated with the hemming adhesive 3, after the adhesive coating is completed, the outer plate 2 is disposed on the inner side of the inner plate assembly 1, that is, the outer plate 2 is positioned on the outer side of the inner plate assembly 1, and the outer plate 2 is connected to the inner plate assembly 1, so that the outer plate 2 is attached to the inner plate assembly 1 and the edge of the outer plate 2 protrudes from the edge of the inner plate assembly 1.
As shown in fig. 3 and 4, in step B, the edge of the outer panel 2 is rolled by a hemming tool so that the edge thereof is folded back toward the inside of the inner panel assembly 1 until the edge of the outer panel 2 forms a hem 4 wrapping the edge of the inner panel assembly 1, the hem 4 including a fillet area 41 having an inside fillet 411 and an outside fillet 412. In this embodiment, the number of times of rolling the edge of the outer panel 2 by the binding tool is three, and in actual production, the number of times of rolling the edge of the outer panel 2 by the binding tool may be determined according to the angle of the outer panel 2 before rolling, and may be four times or five times; the rolling speed of the edge of the outer plate 2 by the edge rolling tool is 50-250 mm/s each time, the rolling pressure is 1000N-2500N, the radius of the external fillet 412 = the radius of the internal fillet 411 + the thickness of the outer plate 2 in the fillet area 41, and after the first rolling forming, the radius of the external fillet 412 is 1.75-2 mm.
In the step C, the whole seam 4 is heated until the temperature of the seam 4 reaches 90-350 ℃, in this embodiment, the seam 4 is heated by using an induction coil, and in actual production, a robot with a laser head may be used to heat the seam 4, or an induction heating table may be used to heat the seam 4, or an oven may be used to heat the seam 4. Wherein, induction coil, induction heating platform and oven are the existing firing equipment who is used for heating the work piece of prior art.
As shown in fig. 5 to 7, in step D, the surface of the bullnose 412 of the binding 4 is rolled by the binding tool until the fillet area 41 of the binding 4 is reduced. In this embodiment, the rolling tool is a rolling head 5 having an axial line, the rolling head 5 first rolls the surface of the bullnose 412 on the outer side of the outer panel 2 along the length direction of the rolled edge 4, and then rolls the surface of the bullnose 412 on the inner side of the outer panel 2 along the length direction of the rolled edge 4; when the surface of the bullnose 412 is rolled, the included angle between the axial line of the rolling head 5 and the plane of the binding 4 is acute, and the binding tool applies a rolling force to the surface of the bullnose 412 on the outer side of the outer panel 2 smaller than a rolling force to the surface of the bullnose 412 on the inner side of the outer panel 2. Wherein the rolling speed of the edge rolling tool is 50-250 mm/s, the rolling pressure is 1000-2500N, and after the second rolling forming, the radius of the external fillet 412 of the edge rolling 4 is less than or equal to 1.5mm.
And D, inspecting the roller edge 4, debugging the whole shape of the roller edge 4 and the surface flatness of the roller edge 4 on site in time, and boxing the well-inspected door cover.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments, or alternatives may be employed, by those skilled in the art, without departing from the spirit or ambit of the invention as defined in the appended claims.
Although the terms inner panel assembly 1, outer panel 2, bead 3, piping 4, fillet area 41, fillet 411, bullnose 412, roll head 5, etc. are used more herein, the possibility of using other terms is not excluded. These terms are used merely to more conveniently describe and explain the nature of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.

Claims (8)

1. A processing method for the border of a door cover, the door cover comprises an inner plate assembly (1) and an outer plate (2) made of metal, and is characterized by comprising the following steps:
A. coating, gluing and splicing: firstly, coating a hem adhesive (3) on an outer plate (2) or an inner plate assembly (1), and then arranging the outer plate (2) on the outer side of the inner plate assembly (1) so that the outer plate (2) is attached to the inner plate assembly (1) and the edge of the outer plate (2) extends out relative to the edge of the inner plate assembly (1);
B. primary roll forming: rolling the edge of the outer plate (2) to enable the edge to be turned over towards the inner side of the inner plate assembly (1) until the edge of the outer plate (2) forms a binding (4) wrapping the edge of the inner plate assembly (1), wherein the binding (4) comprises a fillet area (41) with an inner fillet (411) and an outer fillet (412);
C. heating: heating the edge rolling (4) to 90-350 ℃;
D. and (3) rolling and forming for the second time: rolling the surface of the external fillet (412) of the binding (4) until the fillet area (41) of the binding (4) is reduced;
the binding tool is a rolling head (5) with an axial lead, and when the surface of the external fillet (412) is rolled, the included angle between the axial lead of the rolling head (5) and the plane of the binding (4) is an acute angle.
2. The door cover binding process according to claim 1, wherein in step D, the surface of the bullnose (412) is first rolled on the outside of the outer plate (2) by a binding tool, and then the surface of the bullnose (412) is rolled on the inside of the outer plate (2).
3. The door cover binding process according to claim 2, wherein in step D, the binding tool rolls the surface of the bullnose (412) along the length of the binding (4).
4. The door cover binding process according to claim 2 or 3, wherein in step D, the binding tool applies a smaller rolling force to the surface of the bullnose (412) on the outside of the outer panel (2) than the rolling force to the surface of the bullnose (412) on the inside of the outer panel (2).
5. The door cover binding processing method according to claim 2 or 3, wherein in the step D, the rolling speed of the binding tool is 50mm/s-250mm/s, the rolling pressure is 1000N-2500N, and after the second rolling forming, the radius of the excircle corner (412) of the binding (4) is less than or equal to 1.5mm.
6. A door cover binding process according to any one of claims 1 to 3, characterized in that after step D, the binding (4) is checked and the overall shape of the binding (4) and the surface flatness of the binding (4) are adjusted in time on site.
7. A door cover piping process according to any one of claims 1 to 3, wherein in the step C, the piping (4) of the outer panel (2) is heated by an induction coil.
8. A door cover piping process according to any one of claims 1 to 3, characterized in that in step C, the piping (4) of the outer panel (2) is heated by an induction heating station.
CN202110795579.5A 2021-07-14 2021-07-14 Processing method of door cover edge rolling Active CN113560439B (en)

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Publication number Priority date Publication date Assignee Title
FR3138334A1 (en) * 2022-07-29 2024-02-02 Psa Automobiles Sa METHOD AND DEVICE FOR COMPLEMENTARY FIXING OF AT LEAST TWO SHEETS

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* Cited by examiner, † Cited by third party
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JP3488275B2 (en) * 1993-12-28 2004-01-19 本田技研工業株式会社 Hemming method and apparatus
US8341992B2 (en) * 2010-05-05 2013-01-01 GM Global Technology Operations LLC Roller hemming with in-situ adhesive curing
JP2013248646A (en) * 2012-05-31 2013-12-12 Daihatsu Motor Co Ltd Roller hemming device
KR20160080163A (en) * 2014-12-29 2016-07-07 주식회사 성우하이텍 Hemming method of panel
CN109454140A (en) * 2018-10-26 2019-03-12 安徽巨自动化装备有限公司 The edge knurling process and binding device of aluminium alloy door closure with wide-angle angle of release

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