Unwinding, cutting and forming processes

Abstract

Unwinding, cutting and forming process, which includes the following steps: 1) Unwinding a steel coil, wherein a steel strip unwound from the steel coil is straightened and fed to a cutting area by a clamping roller (5); 2) Laser cutting, wherein the steel coil enters the cutting area, is cut by a laser cutting head (6) by laser cutting to form sheets (100) with a required shape, with waste falling down and being conveyed outwards; 3) Dispensing the sheets (100), characterized by the fact that In step 1) the unwound steel strip is cleaned before it is straightened, wherein in step 3) the dispensed sheets (100) are picked up and conveyed by a magnetic telescopic conveyor belt and then carried by a manipulator or a robot (7) with an external shaft to a punching process, and then the sheets (100) are placed into a lower punching die; or the sheets (100) are picked up by the robot (7) with an external shaft and conveyed directly to the punching process, and then the sheets (100) are placed into the lower punching die; 4) Stamping forming, wherein the sheets (100) are stamped to form workpieces of a specific shape and size, and are edge-cut, punched and trimmed; and 5) Checking the formed workpieces, wherein the formed workpieces are issued, checked and finally placed in a storage (13).

Description

Field of invention

[0001] The present invention relates to the processing of automotive panel coils, and more precisely a developing, cutting and forming process for processing an automotive panel coil to form a three-dimensional stamped plate. background

[0002] A traditional unwinding and cutting line with dies for automotive panels has a production rate of approximately 25 sheets per minute and an annual output of 4,000,000 to 6,000,000 sheets. After flat raw panels are obtained through die cutting, they should be fed to a stamping forming line to produce stamped automotive panel parts. Three-dimensional parts are obtained through stamping forming lines, depending on the investment and production scale. However, a robotic stamping line commonly used in China has a production rate of approximately 5 sheets per minute, a stamping line with a single-arm crossbeam manipulator has a production rate of approximately 10 sheets per minute, and a stamping line with manual feeding has a slower production rate of only 3-5 sheets per minute.This means that an unwinding and cutting line should be able to accommodate several stamping and forming production lines. This mode is typically used in a machining plant or a complete automotive factory, which involves a large factory footprint and a significant investment.

[0003] For example, in the production of small stamped parts for cans with pull-tab lids, Chinese patent application No. CN200920171407.5 summarizes the existing manufacturing solutions for pull-tab lids and proposes automatic multi-pass stamping processes, of which the solution of a synchronous operation of two stamping machines or a multi-pass stamping solution for the production of small parts is suitable and will undoubtedly cause high investment pressure and great difficulties in design and execution.

[0004] A traditional uncoiling and cutting line requires a stacking process after cutting; bundles of sheets are to be transferred after stacking to several punching lines for individual operations; each punching line should be equipped with transfer devices for frequent transfers, such as a forklift, flatbed trailer, or transport truck; and processes such as destacking and material picking and loading should exist upstream of the punching line; and a punching line is generally composed of several multi-press units, or a multi-forming press is used to obtain finished parts. In short, two production lines are needed to implement the forming process: an uncoiling and cutting line and a punching and forming line; the need to repeatedly move the sheets reduces operational efficiency and requires more space for storage and transport to ultimately obtain formed parts.

[0005] DE 10 2009 050 997 A1 discloses a production line for manufacturing a form-hardened component from a stamped blank, wherein the blank is flexibly hot-rolled before form-hardening in order to achieve an adjustment of different thicknesses over the length of the blank.

[0006] DE 10 2009 014 670 A1 discloses a method for the production of press-hardened molded components from sheet steel, wherein stamped blanks from a steel coil are subjected to a temperature process and subsequently to a multi-stage stamping process.

[0007] EP 1586 407A1 discloses a production line in which a coil strip is unwound from a coiling device and fed directly into a roller straightening machine. Subsequently, the straightened steel strip is buffered by means of a looping device and then fed to a laser cutting device to produce laser-cut pieces from the coil strip. The produced laser-cut pieces are placed in containers by a robot.

[0008] CN 2 02 239 211 U discloses a method for sheet metal processing using stamping presses.

[0009] To solve the problem of enormous expenses for molds and the costs of their maintenance and storage resulting from die cutting, and to achieve flexible cutting, laser cutting has become a viable method. However, it remains a technical bottleneck to enable laser cutting to reach the production rate of traditional die cutting, and even with multiple cutting heads to achieve equivalent output, a number of technical difficulties and investment risks still exist.

[0010] Currently, with guaranteed cutting quality, a laser unwinding and cutting line achieves a regular production rate of fewer than a few dozen sheets per minute. This low output precisely meets the requirements of some new, customized, and modified vehicle models without incurring enormous mold development costs or lengthy mold testing. Furthermore, this production rate is exactly the same as that of a conventional stamping line. This enables a process that combines a laser cutting line and a stamping line. Summary

[0011] It is an object of the present invention to provide an unwinding, cutting, and forming process that can achieve the sequential integration of a cutting line and a stamping line, and facilitate adaptation between them. This process can reduce intermediate steps, such as stacking, packaging, transporting, positioning, unpacking, carrying, and centering of sheets and stamped workpieces, and can also reduce the space required for transfer, simplify the workflow, and sequentially link the procedures to directly process a material coil by laser cutting to form formed parts.

[0012] To solve the aforementioned problem, a technical solution of the present invention is provided as follows.

[0013] A developing, cutting and forming process includes the following steps: 1) Unwinding a steel coil, wherein a steel strip unwound from the steel coil is cleaned and straightened and fed to a cutting area by a clamping roller; 2) Laser cutting, wherein the steel coil enters the cutting area, is cut by a laser cutting head to form sheets of a required shape, with waste falling down and being conveyed outwards; 3) Dispensing the sheets, wherein the sheets are picked up and conveyed by a magnetic telescopic conveyor belt and then carried by a manipulator or a robot with an external shaft to a punching process, and then the sheets are placed into a lower punching die; or the sheets are picked up by the robot with an external shaft and conveyed directly to the punching process, and then the sheets are placed into the lower punching die; 4) Stamping forming, wherein the sheets are stamped to form workpieces of a specific shape and size, and edge-cut, punched, and trimmed; and 5) Checking the formed workpieces, whereby the formed workpieces are issued, checked and finally placed in storage.

[0014] Furthermore, in step 1) a looping device is provided between the straightening process and the clamping roller.

[0015] In step 2), the sheets can move dynamically during cutting or be cut in a static state.

[0016] In step 2), at least one laser light source is used with the laser cutting head to perform the laser cutting and trimming.

[0017] In step 2), two laser cutting heads are used for static cutting of plates (hereinafter: sheets).

[0018] In step 2, the waste falls down and is transported outside using a waste chute in combination with a waste conveyor chain to a waste collection container.

[0019] In step 3), the sheets are pretreated before punching, the pretreatment including coating the sheets with oil.

[0020] In step 3), the sheets are first centered and then picked up by the manipulator or robot and carried to the lower stamping die.

[0021] In step 4), the stamping process is simply divided into manual production and automated production, depending on the parts to be manufactured, with a robot or manipulator being used for loading and unloading the material in automated production, and the manipulator comprising a single-arm crossbeam manipulator or a double-arm crossbeam manipulator.

[0022] In step 5), the formed workpieces are output and inspected by being picked up by a robot and subjected to surface quality detection and form and position detection, using a view and visual inspection to detect burrs and defects on parts, the detection tools include a caliper, a micrometer and a test clamping device, and the form and position detection is performed offline or 3D online.

[0023] The advantages of the invention are as follows.

[0024] The present invention is designed based on the comparable manufacturing yield of laser cutting and stamping. This method can reduce intermediate steps, such as stacking, packaging, transporting, positioning, unpacking, carrying, and centering planar sheets and stamped workpieces, and can also reduce the space required for transfer, simplify the workflow, and combine the procedures sequentially to directly process a material coil by laser cutting to form formed parts. Brief description of the drawings Fig. Figure 1 is a schematic diagram of a first embodiment of the present invention; Fig. Figure 2 is a schematic diagram of a second embodiment of the present invention; Fig. 3 and Fig. Figure 4 shows schematic diagrams of a developing and cutting forming process of a first embodiment of the present invention. Detailed description

[0025] Referring to Fig. Figure 1 shows a schematic diagram of a first embodiment of the present invention. A developing, cutting, and forming process of the present invention comprises the following steps. 1) Unwinding a steel coil, wherein a steel strip unwound from the steel coil is subjected to cleaning and straightening 3 and passes through a cutting area via a looping device 4 and a clamping roller 5 (hereinafter also referred to as: clamping device 5); 2) Laser cutting, wherein the steel coil enters the cutting area and is cut by a laser cutting head 6 to produce sheets 100 (see Fig. 3 and Fig. 4) to form with a required shape, whereby waste falls down and is transported outwards; 3) Dispensing the sheets 100, wherein the sheets 100 are picked up and transported by a magnetic telescopic conveyor belt and then carried by means of a manipulator or a robot 7 with an external shaft to a punching process, and then the sheets 100 are placed into a lower punching die; 4) Stamping forming, wherein the sheets are stamped to form workpieces of a specific shape and size, and are edge-cut, punched, and trimmed; and 5) Checking the formed workpieces, whereby the formed workpieces are issued, checked and finally placed in storage 13.

[0026] According to this embodiment, in step 2) two laser cutting heads 6 are used for static cutting of the sheets 100.

[0027] In step 2, the waste falls down and is transported outside using a waste chute in combination with a waste conveyor chain to a waste collection container.

[0028] In step 3), the sheets 100 are picked up by robot 7 with an external shaft and conveyed directly to the lower die. The pretreatment before die-cutting includes cleaning the sheets 100 and coating them with oil. The sheets 100 are centered by a manipulator or robot 10, which picks up the sheets 100 during loading, and then carried by the manipulator or robot 10 to the lower die.

[0029] In step 4), the stamping process is simply divided into manual production and automated production, depending on the parts to be manufactured, with a robot or manipulator being used for loading and unloading the material in automated production, and the manipulator comprising a single-arm crossbeam manipulator or a double-arm crossbeam manipulator.

[0030] In step 5), the formed workpieces are ejected and inspected by being picked up by a robot 12 (hereinafter also referred to as: unloading robot 12) and subjected to surface quality detection and form and position detection, using a view and visual inspection to detect burrs and defects on parts, the detection tools include a caliper, a micrometer and a test clamping device, and the form and position detection is performed off-line or 3D on-line.

[0031] More precisely, a cyclical operating mode over the entire street according to a first embodiment of the present invention is as follows.

[0032] A material coil is unwound by an unwinding machine 1 and fed into a sheet conveyor cleaning machine 2, undergoes straightening 3, passes over a looping device 4 and is then clamped by a clamping device 5 and then enters a laser cutting head 6 for cutting and waste removal; the resulting sheets 100 are transferred by a robot 7 (hereinafter also referred to as: carrying robot 7) to a platform for sheet cleaning 8 and oil coating 9; and another robot 10 (hereinafter also referred to as: picking robot 10) picks up the sheets 100 and places them in a punching machine 11 (hereinafter also referred to as: press 11), and an unloading robot 12 picks up the punched sheets 100 and places them in the storage 13.

[0033] As in the Fig. 3 and Fig. As shown in Figure 4, two laser cutting heads 6 are used for cutting in this embodiment. The sheet conveyor enters a static cutting area after undergoing the unwinding and preparation processes. A first laser cutting head partially cuts a sheet 100 in a first cutting area A. The sheet conveyor advances by one step corresponding to one sheet 100. A second laser cutting head further cuts the remainder of the sheet 100 in a second cutting area B to obtain sheets 100 (hereinafter also referred to as output sheets). At the same time, the laser cutting head partially cuts another sheet 200 in the first cutting area A. This process is repeated.

[0034] After the two laser cutting heads 6 have completed the cutting operations in this area, the conveyor belt advances one step, and the cutting continues. The sheets 100 and 200 are then carried by the transport robot 7 with an external shaft to a punching preparation process for cleaning and oiling. A press 11 then performs the punching, and acceptable products are placed in storage 13 after inspection.

[0035] Furthermore, the first laser cutting head can also partially cut more than two sheets of 100, and the second laser cutting head cuts the rest of the sheets of 100 to obtain output sheets.

[0036] Fig. Figure 2 is a schematic diagram of a system solution of a second embodiment according to the present invention. In order to obtain a production rate that is the same between the production lines, the system solution, as shown in Figure 2, can be used. Fig.Figure 2 shows that a single cutting head is used for the cutting and forming of various sheet metal parts 100, and a single cutting head is used in one cutting and trimming area. For example, for a planar sheet metal part 100 with a small cutting size or a simple cutting shape (a rectangular or trapezoidal shape), a dynamic, continuous cutting process with a single laser can be used without the use of a looping device 4.

Claims

[1] Unfolding, cutting and forming process comprising the steps: 1) Unwinding a steel coil, wherein a steel strip unwound from the steel coil is straightened and fed to a cutting area by a clamping roller (5); 2) Laser cutting, wherein the steel coil enters the cutting area, is cut by a laser cutting head (6) by laser cutting to form sheets (100) with a required shape, with waste falling down and being conveyed outwards; 3) Dispensing the sheets (100), characterized by , that In step 1) the unwound steel strip is cleaned before it is straightened, wherein in step 3) the dispensed sheets (100) are picked up and conveyed by a magnetic telescopic conveyor belt and then carried by a manipulator or a robot (7) with an external shaft to a punching process, and then the sheets (100) are placed into a lower punching die; or the sheets (100) are picked up by the robot (7) with an external shaft and conveyed directly to the punching process, and then the sheets (100) are placed into the lower punching die; 4) Stamping forming, wherein the sheets (100) are stamped to form workpieces of a specific shape and size, and are edge-cut, punched and trimmed; and 5) Checking the formed workpieces, wherein the formed workpieces are issued, checked and finally placed in a storage (13). [2] Unwinding, cutting and forming method according to claim 1, wherein in step 1) a looping device (4) is provided between the straightening and the clamping roller (5). [3] Unwinding, cutting and forming process according to claim 1, wherein in step 2) the sheets (100) move dynamically during laser cutting or are laser cut in a static state. [4] Unwinding, cutting and forming process according to claim 1, characterized by , that in step 2) at least one laser light source is used with the laser cutting head (6) to perform the laser cutting. [5] Unfolding, cutting and forming process according to claim 1, wherein in step 2) two laser cutting heads (6) are used for static laser cutting of the sheets (100). [6] Unwinding, cutting and forming method according to claim 1, wherein in step 2) the waste falls down and is conveyed outwards by using a waste chute in combination with a waste conveying chain to a waste collection container. [7] Unwinding, cutting and forming process according to claim 1, wherein in step 3) the sheets (100) are pretreated before the punching process, the pretreatment comprising coating the sheets (100) with oil. [8] Unwinding, cutting and forming method according to claim 1, wherein in step 3) the sheets (100) are first centered and then picked up by a manipulator or picking robot (10) and carried to the lower die. [9] Unwinding, cutting and forming process according to claim 1, wherein in step 4) the stamping forming is simply divided into a manual production and an automated production, depending on the parts to be produced, wherein a robot or a manipulator is used for loading and unloading the material in the automated production. [10] Unwinding, cutting and forming method according to claim 9, wherein the robot or manipulator comprises a single-arm crossbeam manipulator or a two-arm crossbeam manipulator. [11] Unwinding, cutting and forming method according to claim 1, wherein in step 5) the formed workpieces are ejected and inspected by being picked up by an unloading robot (12) and subjected to surface quality detection and shape and position detection, wherein a view and a visual inspection are used to detect burrs and defects on parts, the detection tools comprise a caliper, a micrometer and a test clamping device, and the shape and position detection is performed off-line or 3D on-line.

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