A method for processing high-strength outer arc corners of rectangular tubes based on laser cutting machine

Abstract

The present invention proposes a method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine, S1: determining the outer width W1, outer height H1, inner width W2, outer height H2 of the rectangular tube and obtaining the wall thickness T; defining two parallel side surfaces separated by the outer width W1 as the first surface (10) and the second surface (11); defining two parallel side surfaces separated by the outer height H1 as the third surface (13) and the fourth surface (14); S2: subtracting the wall thickness T from the outer width W1 to obtain the radius parameter r1; taking the radius parameter r1 and the required bending angle a1 as references to obtain the arc length C1 under the radius and angle; S3: determining the front end material taking length L1 of the rectangular tube, and adding the arc length C1 to the rear end of the front end material taking length L1 after unfolding to form a cutting section (20) in the length direction of the rectangular tube. The present invention has the advantages of forming an outer arc corner by cutting, bending and welding the profile without cutting, and ensuring the overall strength and aesthetics.

Description

Technical Field

[0001] The invention relates to the field of laser cutting processing of profiles, and in particular to a method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine. Background Art

[0002] In the production process of furniture tables and chairs, the main body is often made by cutting profiles and then welding them. The traditional supporting frame is generally made by cutting the end face of the profile at 45 degrees and then welding it, or by welding the end face of one profile to the side wall of another profile. In addition to the disadvantage of poor overall strength, this structure often has sharp top corners, which can easily cause injuries when bumped. If the top corner needs to be designed as an arc, it is often necessary to use an adapter for assembly, which has problems such as poor strength, complicated process, and high production cost. Summary of the invention

[0003] Based on the above problems, the purpose of the present invention is to provide a method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine by using non-cutting cutting of rectangular tubes to achieve rounded corner docking while meeting the strength and overall installation accuracy.

[0004] In view of the above problems, the following technical solutions are provided: A method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine, comprising the following steps:

[0005] S1: Determine the outer width W1, outer height H1, inner width W2, outer height H2 of the rectangular tube and obtain the wall thickness T of the rectangular tube; define the two parallel side surfaces separated by the outer width W1 as the first side and the second side; define the two parallel side surfaces separated by the outer height H1 as the third side and the fourth side;

[0006] S2: The radius parameter r1 is obtained by subtracting the wall thickness T of the rectangular tube from the outer width W1; the arc length C1 at the radius and angle is obtained by taking the radius parameter r1 and the required bending angle a1 as reference;

[0007] S3: Determine the front end material taking length L1 of the rectangular tube, and add the arc length C1 to the rear end of the front end material taking length L1 after expansion to form a cutting section in the length direction of the rectangular tube;

[0008] S4: a blanking area is cut out on the cutting section; one end of the cutting section is used as the first virtual reference section, and a first cutting slit is formed at the intersection of the first virtual reference section and the third surface, wherein the length of the first cutting slit is equal to the radius parameter r1; one end of the first cutting slit is cut to the outer wall of the first surface, and the other end is cut to be flush with the inner wall of the second surface, and then cut toward the other end of the cutting section to form a second cutting slit; the other end of the cutting section is used as the second virtual reference section, and a third cutting slit is cut at the intersection of the first surface and the second virtual reference section as the axis of the radius parameter r1, wherein the third One end of the cutting slit is butted against the second cutting slit in a tangential manner and the tangent point coincides with the second virtual reference section; the other end of the third cutting slit is cut to the outer wall of the first surface along the radius parameter r1; the first cutting slit and the third cutting slit are cut to the virtual mid-plane between the third surface and the fourth surface through the fourth cutting slit and the fifth cutting slit on the first surface, and the fourth cutting slit and the fifth cutting slit are connected along the virtual mid-plane through the sixth cutting slit; the first cutting slit, the second cutting slit, the third cutting slit, the fourth cutting slit, the fifth cutting slit, and the sixth cutting slit are connected and closed to form a blanking area;

[0009] S5: There are two blanking areas, and the other blanking area is obtained by mirroring the virtual mid-dividing plane between the first virtual reference cross section and the second virtual reference cross section as a mirror plane and then mirroring the virtual mid-dividing plane as a mirror plane to the fourth surface;

[0010] S6: The fifth cutting seam and the sixth cutting seam of the two material cutting areas are connected at their junctions by a seventh cutting seam cut along the virtual mid-plane; after removing the two material cutting areas, a rounded corner covering surface is formed on the second surface of the material cutting section;

[0011] S7: Cut the rectangular tube according to the size, leaving the rear end material length L3; bend the front end material length L1 section and the rear end material length L3 section toward the first surface, and make the rounded corner covering surface fit with the third cutting seam of each material cutting area; at the same time, make the first surface fit with the first cutting seam and the fourth cutting seam of the corresponding material cutting area;

[0012] S8: welding the cut seams after bending;

[0013] S9: Grind the weld to make it smooth.

[0014] Furthermore, the first cutting seam, the second cutting seam, the third cutting seam, the fourth cutting seam, the fifth cutting seam, the sixth cutting seam and the seventh cutting seam are all cut by a laser tube cutting machine.

[0015] Furthermore, the laser tube cutting machine includes a loading mechanism, a feeding mechanism, a main chuck fixture, a discharge end and a laser cutting head, and the discharge end is provided with a sub-chuck fixture; the rectangular tube is sent to the feeding mechanism via the loading mechanism, and then sent to the discharge end from the main chuck fixture by the feeding mechanism, and the laser cutting head is located above the rectangular tube between the main chuck fixture and the discharge end; the sub-chuck fixture is coaxially arranged with the main chuck fixture and the rotation direction is synchronized with the main chuck fixture.

[0016] Furthermore, a profile lifting sleeve is mounted on the auxiliary chuck fixture, and one end of the rectangular tube located at the discharge end is inserted into the profile lifting sleeve and is slidably arranged with a gap with the inner wall of the profile lifting sleeve.

[0017] Furthermore, the length of the profile lifting sleeve is not less than the sum of the front end material taking length L1 and the cutting section length.

[0018] Furthermore, a guiding bevel is provided at the junction of the inner wall and the end surface of one end of the profile lifting sleeve facing the main chuck fixture.

[0019] Furthermore, the cross-sectional profile of the inner cavity of the profile lifting sleeve corresponds to that of the rectangular tube.

[0020] Furthermore, after the material is unloaded in the unloading area, a supporting surface is formed on the first surface at the positions of the sixth cutting seam and the seventh cutting seam; the end of the supporting surface facing the length direction of the rectangular tube is abutted against the inner wall of the second surface after bending in step S7, and the front end material collection length L1 section and the rear end material collection length L3 section of the rectangular tube remain conductive after bending and welding are completed.

[0021] Furthermore, between steps S7 and S8, the junction of the two supporting surfaces is pre-fixed by spot welding at the angle position of the first surface.

[0022] Furthermore, the bending angle a1 is 90 degrees.

[0023] Beneficial effects of the present invention:

[0024] 1. There is no need to completely cut the rectangular tube during production, which ensures the overall accuracy of the subsequent bending and welding;

[0025] 2. The blanking area is formed by laser cutting, so that the rounded corners are formed into outer arc corners when bending, which ensures the overall aesthetics of the product and avoids the harm to users when sharp corners collide;

[0026] 3. The two material removal areas are arranged radially symmetrically through two mirror planes, which can effectively disperse the stress after bending and welding, greatly improving the strength of the weld;

[0027] 4. The two supporting surfaces formed are displaced from each other after bending, which not only avoids the formation of a closed area inside the rectangular tube (ensuring air circulation and preventing moisture accumulation from causing rust in the later use of the product), but also improves the overall strength and rigidity of the corners;

[0028] 5. Compared with the adapter type connection method, the arc corner has lower cost and higher strength and stability;

[0029] 6. Convenient welding, grinding the weld after welding can achieve seamless effect;

[0030] 7. The deformation is small after laser cutting, and the overall surface can be directly painted after welding and grinding;

[0031] 8. The structure with right angles on the inside and arcs on the outside has a good overall visual effect, giving people a one-piece visual effect;

[0032] 9. According to the assembly requirements, several pairs of blanking areas can be cut in the length direction of the rectangular tube, and the export font frame or other complex shape frames can be processed by bending and welding;

[0033] 10. After bending, the two support surfaces are mutually offset in the inner cavity of the rectangular tube corner. When additional table legs, brackets and other parts are needed at the corner in the later stage, they can be used as additional welding or fixing points to improve the connection strength (reference Fig.16 , Fig.17 ). BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention.

[0035] Figure 2 It is a schematic diagram of the three-dimensional structure of the slit of the rectangular tube of the present invention from the first perspective.

[0036] Figure 3 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention after removing the blanking area 30 from the first perspective.

[0037] Figure 4 It is a schematic diagram of the three-dimensional structure of the slit of the rectangular tube of the present invention from a second viewing angle.

[0038] Figure 5 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention after removing the blanking area 30 from a second viewing angle.

[0039] Figure 6 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention after removing the blanking area 30 from the third viewing angle.

[0040] Figure 7 It is a schematic diagram of the first perspective full cross-section stereoscopic structure after the blanking area 30 of the present invention is removed.

[0041] Figure 8 It is a schematic diagram of the full cross-section three-dimensional structure from a second viewing angle after the blanking area 30 of the present invention is removed.

[0042] Fig. 9 It is a schematic diagram of the three-dimensional structure from a first perspective during the bending process of the rectangular tube of the present invention.

[0043] Fig.10 It is a schematic diagram of the three-dimensional structure from a second perspective during the bending process of the rectangular tube of the present invention.

[0044] Fig.11 This is a schematic diagram of the three-dimensional structure from a first perspective after the rectangular tube of the present invention is bent.

[0045] Fig.12 It is a schematic diagram of the three-dimensional structure from a second perspective after the rectangular tube of the present invention is bent.

[0046] Fig.13 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention after the bending is completed in full section from the first perspective.

[0047] Fig.14 It is a schematic diagram of the three-dimensional structure of the rectangular tube of the present invention after the bending is completed in full section from a second viewing angle.

[0048] Fig.15 It is a schematic diagram of the three-dimensional structure of the support surface 101 after the rectangular tube of the present invention is bent.

[0049] Fig.16 It is a schematic diagram of the three-dimensional structure when table legs 40 are added to the corners of the present invention.

[0050] Fig.17 It is a schematic diagram of the three-dimensional structure of the state in which the support surface 101 and the outer wall of the table leg 40 are in abutment with each other when a table leg 40 is added at the corner of the present invention. DETAILED DESCRIPTION

[0051] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0052] refer to Figures 1 to 17 ,like Figures 1 to 17 A method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine is shown, comprising the following steps:

[0053] S1: Determine the outer width W1, outer height H1, inner width W2, outer height H2 of the rectangular tube and obtain the wall thickness T of the rectangular tube; define the two parallel side surfaces separated by the outer width W1 as the first surface 10 and the second surface 11; define the two parallel side surfaces separated by the outer height H1 as the third surface 13 and the fourth surface 14;

[0054] S2: The radius parameter r1 is obtained by subtracting the wall thickness T of the rectangular tube from the outer width W1; the arc length C1 at the radius and angle is obtained by taking the radius parameter r1 and the required bending angle a1 as reference;

[0055] S3: Determine the front end material taking length L1 of the rectangular tube, and add the arc length C1 to the rear end of the front end material taking length L1 after unfolding to form a cutting section 20 in the length direction of the rectangular tube;

[0056] S4: a blanking area 30 is cut out on the cutting section 20; one end of the cutting section 20 is used as the first virtual reference section 21, and a first cutting slit 31 is formed at the junction of the first virtual reference section 21 and the third surface 13, and the length of the first cutting slit 31 is equal to the radius parameter r1; one end of the first cutting slit 31 is cut to the outer wall of the first surface 10, and the other end is cut to be flush with the inner wall of the second surface 11, and then cut toward the other end of the cutting section 20 to form a second cutting slit 32; the other end of the cutting section 20 is used as the second virtual reference section 22, and a third cutting slit 33 is cut at the junction of the first surface 10 and the second virtual reference section 22 as the axis 90 with the radius parameter r1, and the third cutting slit 33 is The end is butted with the second cutting slit 32 in a tangential manner and the tangent point 221 coincides with the second virtual reference section 22, and the other end of the third cutting slit 33 is cut to the outer wall of the first surface 10 along the radius parameter r1; the first cutting slit 31 and the third cutting slit 33 are cut on the first surface 10 through the fourth cutting slit 34 and the fifth cutting slit 35 to the virtual mid-plane 15 between the third surface 13 and the fourth surface 14, and the fourth cutting slit 34 and the fifth cutting slit 35 are connected along the virtual mid-plane 15 through the sixth cutting slit 36; the first cutting slit 31, the second cutting slit 32, the third cutting slit 33, the fourth cutting slit 34, the fifth cutting slit 35, and the sixth cutting slit 36 ​​are connected and closed to form a blanking area 30;

[0057] S5: There are two blanking areas 30, and another blanking area 30 is obtained by mirroring the virtual mid-plane between the first virtual reference cross section 21 and the second virtual reference cross section 22 as a mirror plane, and then mirroring the virtual mid-plane 15 as a mirror plane onto the fourth surface 14;

[0058] S6: The fifth cutting seam 35 and the sixth cutting seam 36 of the two material-cutting areas 30 are connected at their junctions by a seventh cutting seam 37 cut along the virtual mid-plane 15; after removing the two material-cutting areas 30, a rounded corner covering surface 111 is formed on the second surface 11 of the material-cutting section 20;

[0059] S7: Cut the rectangular tube according to the size to leave the rear end material length L3; bend the front end material length L1 section and the rear end material length L3 section toward the first surface 10 and make the rounded covering surface 111 fit the third cutting seam 33 of each material removal area 30; at the same time, make the first surface 10 fit the first cutting seam 31 and the fourth cutting seam 34 of the corresponding material removal area 30;

[0060] S8: Weld the cut seams after bending.

[0061] In this embodiment, the first cutting slit 31 , the second cutting slit 32 , the third cutting slit 33 , the fourth cutting slit 34 , the fifth cutting slit 35 , the sixth cutting slit 36 ​​, and the seventh cutting slit 37 are all cut by a laser tube cutting machine.

[0062] In this embodiment, the laser tube cutting machine includes a loading mechanism, a feeding mechanism, a main chuck fixture, a discharge end and a laser cutting head. The discharge end is provided with a sub-chuck fixture; the rectangular tube is sent to the feeding mechanism via the loading mechanism, and then sent to the discharge end from the main chuck fixture by the feeding mechanism. The laser cutting head is located above the rectangular tube between the main chuck fixture and the discharge end; the sub-chuck fixture is coaxially arranged with the main chuck fixture and the rotation direction is synchronized with the main chuck fixture (the laser tube cutting machine is a prior art, so it is not shown in the attached drawings).

[0063] In the above structure, due to the cutting of the blanking area 30, the rectangular tube presents a cantilever beam effect on the main chuck fixture and is prone to drooping. The auxiliary chuck fixture is coaxially arranged with the main chuck fixture and the rotation direction is synchronized with the main chuck fixture. The auxiliary chuck fixture is used to lift and constrain the outer hanging end of the rectangular tube to reduce or avoid the edge shape.

[0064] In this embodiment, a profile lifting sleeve is clamped on the auxiliary chuck fixture, and one end of the rectangular tube located at the discharge end is inserted into the profile lifting sleeve and is slidably arranged with a gap with the inner wall of the profile lifting sleeve.

[0065] In the above structure, the rectangular tube is constrained by the profile lifting sleeve during cutting, and can slide in the profile lifting sleeve during feeding in the length direction of the rectangular tube, thereby preventing the rounded corner covering surface 111 from being deformed after the material is taken out of the unloading area 30 .

[0066] In this embodiment, the length of the profile lifting sleeve is not less than the sum of the front end material taking length L1 and the length of the cutting section 20.

[0067] In this embodiment, a guiding bevel is provided at the junction of the inner wall and the end surface of the end of the profile lifting sleeve facing the main chuck fixture.

[0068] In the above structure, it is convenient for the auxiliary chuck fixture to move toward the main chuck fixture to guide the rectangular tube into the profile lifting sleeve when connecting the end of the rectangular tube.

[0069] In this embodiment, the cross-sectional profile of the inner cavity of the profile lifting sleeve corresponds to that of the rectangular tube.

[0070] In the above structure, the profile lifting sleeve is preferably made of polytetrafluoroethylene to reduce friction.

[0071] In this embodiment, after the unloading area 30 unloads the material, a support surface 101 is formed on the first surface 10 at the positions of the sixth cutting seam 36 and the seventh cutting seam 37; the end of the support surface 101 facing the length direction of the rectangular tube is abutted against the inner wall of the second surface 11 after bending in step S7, and the front end material collection length L1 section and the rear end material collection length L3 section of the rectangular tube remain conductive after bending and welding are completed.

[0072] In this embodiment, between steps S7 and S8 , the junction of the two supporting surfaces 101 is pre-fixed by spot welding at the position of the included angle 102 of the first surface 10 .

[0073] In the above structure, the spot welding pre-fixation can constrain the bending angle of the rectangular tube after bending, so as to facilitate the full welding of each weld in the later stage.

[0074] In this embodiment, the bending angle a1 is 90 degrees.

[0075] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications of the above assumptions should also be regarded as the scope of protection of the present invention.

Claims

1. A method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine, comprising the following steps: S1: Determine the outer width W1, outer height H1, inner width W2, outer height H2 of the rectangular tube and obtain the wall thickness T of the rectangular tube; define the two parallel side surfaces separated by the outer width W1 as the first surface (10) and the second surface (11); define the two parallel side surfaces separated by the outer height H1 as the third surface (13) and the fourth surface (14); S2: The radius parameter r1 is obtained by subtracting the wall thickness T of the rectangular tube from the outer width W1; the arc length C1 at the radius and angle is obtained by taking the radius parameter r1 and the required bending angle a1 as reference; S3: determining the front end material removal length L1 of the rectangular tube, and adding the arc length C1 to the rear end of the front end material removal length L1 after unfolding to form a cutting section (20) in the length direction of the rectangular tube; S4: a cutting area (30) is cut out on the cutting section (20); one end of the cutting section (20) is used as a first virtual reference section (21), and a first cutting slit (31) is formed at the junction of the first virtual reference section (21) and the third surface (13), wherein the length of the first cutting slit (31) is equal to the radius parameter r1; one end of the first cutting slit (31) is cut to the outer wall of the first surface (10), and the other end is cut to be flush with the inner wall of the second surface (11), and then cut toward the other end of the cutting section (20) to form a second cutting slit (32); the other end of the cutting section (20) is used as a second virtual reference section (22), and a third cutting slit (33) is cut at the junction of the first surface (10) and the second virtual reference section (22) as an axis (90) with a radius parameter r1, wherein one end of the third cutting slit (33) is aligned with the second virtual reference section (22). The cutting slits (32) are butted in a tangential manner and the tangent point (221) coincides with the second virtual reference section (22); the other end of the third cutting slit (33) is cut along the radius parameter r1 to the outer wall of the first surface (10); the first cutting slit (31) and the third cutting slit (33) are cut on the first surface (10) through the fourth cutting slit (34) and the fifth cutting slit (35) to the virtual center plane (15) between the third surface (13) and the fourth surface (14); the fourth cutting slit (34) and the fifth cutting slit (35) are connected along the virtual center plane (15) through the sixth cutting slit (36); the first cutting slit (31), the second cutting slit (32), the third cutting slit (33), the fourth cutting slit (34), the fifth cutting slit (35) and the sixth cutting slit (36) are connected and closed to form a blanking area (30); S5: There are two blanking areas (30), and the other blanking area (30) is obtained by mirroring the virtual center plane between the first virtual reference cross section (21) and the second virtual reference cross section (22) as a mirror plane, and then mirroring the virtual center plane (15) as a mirror plane to the fourth surface (14); S6: The fifth cutting seam (35) and the sixth cutting seam (36) of the two material removal areas (30) are connected at their junctions by a seventh cutting seam (37) cut along the virtual mid-plane (15); after removing the two material removal areas (30), a rounded corner covering surface (111) is formed on the second surface (11) of the material removal section (20); S7: cutting the rectangular tube according to the size to leave a rear end material length L3; bending the front end material length L1 section and the rear end material length L3 section toward the first surface (10) and making the rounded corner covering surface (111) fit the third cutting seam (33) of each material removal area (30); and at the same time making the first surface (10) fit the first cutting seam (31) and the fourth cutting seam (34) of the corresponding material removal area (30); S8: welding the cut seams after bending; S9: Grind the weld to make it smooth.

2. According to claim 1, a method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine is characterized in that: The first cutting seam (31), the second cutting seam (32), the third cutting seam (33), the fourth cutting seam (34), the fifth cutting seam (35), the sixth cutting seam (36), and the seventh cutting seam (37) are all cut by a laser tube cutting machine.

3. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 2, characterized in that: The laser tube cutting machine includes a loading mechanism, a feeding mechanism, a main chuck fixture, a discharge end and a laser cutting head. The discharge end is provided with a sub-chuck fixture. The rectangular tube is sent to the feeding mechanism via the loading mechanism, and then sent to the discharge end from the main chuck fixture by the feeding mechanism. The laser cutting head is located above the rectangular tube between the main chuck fixture and the discharge end. The sub-chuck fixture is coaxially arranged with the main chuck fixture and its rotation direction is synchronized with that of the main chuck fixture.

4. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 3, characterized in that: A profile lifting sleeve is clamped on the auxiliary chuck fixture, and one end of the rectangular tube located at the discharge end is inserted into the profile lifting sleeve and is slidably arranged with a gap with the inner wall of the profile lifting sleeve.

5. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 4, characterized in that: The length of the profile lifting sleeve is not less than the sum of the front end material taking length L1 and the length of the cutting section (20).

6. A method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 4 or 5, characterized in that: A guiding bevel is arranged at the junction of the inner wall and the end surface of one end of the profile lifting sleeve facing the main chuck fixture.

7. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 4, characterized in that: The cross-sectional profile of the inner cavity of the profile lifting sleeve corresponds to that of the rectangular tube.

8. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 1, characterized in that: After the material is discharged from the material discharge area (30), a support surface (101) is formed on the first surface (10) at the locations of the sixth cutting seam (36) and the seventh cutting seam (37); one end of the support surface (101) facing the length direction of the rectangular tube abuts against the inner side wall of the second surface (11) after being bent in step S7, and the front end material collection length L1 section and the rear end material collection length L3 section of the rectangular tube are kept conductive after the bending and welding are completed.

9. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 1, characterized in that: Between steps S7 and S8, the junction of the two supporting surfaces (101) is pre-fixed by spot welding at the position of the included angle (102) of the first surface (10).

10. The method for processing high-strength outer arc corners of rectangular tubes based on a laser cutting machine according to claim 1, characterized in that: The bending angle a1 is 90 degrees.

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