Cold roll forming equipment for special-shaped steel pipe

Abstract

The invention relates to the technical field of steel pipe bending equipment, in particular to cold roll forming equipment for special-shaped steel pipes, which comprises a worktable, a bending mechanism and a plurality of retaining mechanisms. The bending mechanism comprises a pipe bending die and a clamping block, the retaining mechanism comprises a retaining frame and four clamping pieces, the retaining frame is installed on the pipe bending die, the four clamping pieces are all installed on the retaining frame, a bending column is arranged on the pipe bending die, and the bending column and the pipe bending die are coaxially arranged. According to the cold roll forming equipment for the special-shaped steel pipe, the bending mechanism and the retaining mechanisms are arranged on the workbench, and after bending is completed, the multiple retaining mechanisms are all located on the bending section, so that the side face, close to the side of the pipe bending die in the second direction, of the square pipe is not prone to generating wrinkles towards the side close to the central axis of the square pipe, and the machining efficiency is improved. The side face, close to one side of the clamping block in the second direction, of the square pipe is not prone to being flattened, the influence on the inner diameter of the square pipe after bending is reduced, and the bending quality of the square pipe is improved.

Description

Technical Field

[0001] The invention relates to the technical field of steel pipe bending equipment, and in particular to cold bending forming equipment for special-shaped steel pipes. Background Art

[0002] Special-shaped steel pipes refer to steel pipes with non-circular cross-sections, such as square pipes. Special-shaped steel pipes are widely used in various structural parts, tools and mechanical parts. Compared with round pipes, special-shaped steel pipes generally have larger moments of inertia and section modulus, greater bending and torsion resistance, which can greatly reduce the weight of the structure and save steel.

[0003] Extrusion, oblique die rolling and cold bending are all effective methods for producing special-shaped steel pipes. Among them, when cold bending square steel pipes, defects are prone to occur during the bending process. The specific manifestations of the defects are: the inner side of the steel pipe is wrinkled, the outer side is flattened, and the inner diameter of the steel pipe after bending changes. The existence of bending defects will have a great negative impact on the quality of bent pipe fittings. On the one hand, it may cause a reduction in cross-sectional area, thereby increasing the resistance to fluid flow. On the other hand, it also affects the function of the pipe fittings in the structure and affects the normal use of the bent pipe fittings. Summary of the invention

[0004] The invention provides a cold bending forming device for special-shaped steel pipes, so as to solve the problem that the inner side of the steel pipe is easily wrinkled and the outer side is flattened when the existing cold bending forming device bends the opposite pipe, thereby affecting the normal use of the bent pipe fittings.

[0005] A cold bending forming device for a special-shaped steel pipe of the present invention adopts the following technical scheme: a cold bending forming device for a special-shaped steel pipe, used for bending a square pipe, comprises a workbench, a bending mechanism and a plurality of holding mechanisms; the bending mechanism comprises a pipe bending die and a clamping block, the pipe bending die can be rotatably installed on the workbench around a first direction, the first direction is a vertical direction; the clamping block is installed on the pipe bending die, the clamping block can move along a second direction to a side close to the pipe bending die to close the mold with the pipe bending die, the second direction is perpendicular to the first direction, and the second direction is a horizontal direction; a clamping space for clamping the square pipe is defined between the clamping block and the pipe bending die after the mold is closed, the lower pipe is arranged along a third direction in the initial state, and a plurality of holding mechanisms are arranged in sequence along the third direction on the pipe bending die, and the third direction is respectively opposite to the first direction The second direction is perpendicular to the second direction, and the third direction is horizontal. The holding mechanism includes a holding frame and four clamping members. The holding frame is installed on the tube bending die, and the four clamping members are all installed on the holding frame. The four clamping members are respectively located in four right-angle areas of the square tube, and each clamping member can apply a force toward one side of the central axis of the square tube to the right-angle area corresponding to it, and make the four side surfaces of the square tube in the right-angle area in the third direction become arc surfaces, and the concave side of the arc surface is arranged toward the central axis of the square tube; a bending column is arranged on the tube bending die, and the bending column is coaxially arranged with the tube bending die. The bent part of the square tube is called a bending section. The bending column can drive multiple holding frames to rotate around the first direction, and make the multiple holding frames evenly distributed on the bending section along the axial direction of the bending section.

[0006] Furthermore, the bending column has a head end and a tail end, which are arranged in sequence in the rotation direction of the bending die, and the head end is located in front of the tail end in the rotation direction of the bending die; and the diameter of the bending column gradually increases from the head end to the tail end; multiple retaining frames are slidably installed on the bending die, and each retaining frame is provided with a matching groove, which is slidably matched with the bending column. In the initial state, multiple retaining frames are slidably installed on the head end side of the bending column, and the sizes of the multiple matching grooves are different, and the size of the matching groove close to the head end of the bending column is smaller than the size of the matching groove close to the tail end of the bending column. Therefore, in the process of the bending column rotating with the bending die, when the diameter of the bending column can match the diameter of the matching groove, the retaining frame where the matching groove is located can rotate synchronously with the bending column around the first direction.

[0007] Furthermore, two adjacent retaining frames are connected via a first elastic member.

[0008] Furthermore, the retaining frame includes a first frame and a second frame, the first frame is slidably installed on the tube bending mold, the second frame is connected to the first frame, and the second frame can move along the second direction toward or away from the side of the first frame, and two clamping members are respectively arranged on the first frame and the second frame, and the two clamping members on the first frame and the two clamping members on the second frame are arranged face to face in the second direction.

[0009] Furthermore, the clamping member is a clamping wheel, which can be rotatably arranged around a reference axis, and the reference axis is the tangent direction of the right-angle region of the square tube where the clamping wheel is located; and the two clamping wheels on the first frame can approach each other along the first direction, and the two clamping wheels on the second frame can approach each other along the first direction.

[0010] Furthermore, it also includes a limiting mechanism, which includes a driving block. The driving block can move along the second direction toward or away from one side of the square tube, and the driving block can abut against the square tube when moving along the second direction toward one side of the square tube.

[0011] Furthermore, the limiting mechanism also includes a limiting block, which is installed on the driving block and can move synchronously with the driving block. A slot is provided on the limiting block. When the limiting block moves along the second direction toward the side close to the square tube, the slot and the square tube can slide together. The limiting block can move along the third direction relative to the driving block.

[0012] Furthermore, a limiting groove is provided on the tube bending die, and the bent square tube can abut against the limiting groove.

[0013] Furthermore, three holding mechanisms are provided.

[0014] Furthermore, a slide groove is provided on the tube bending die, the slide groove is coaxially arranged with the tube bending die, and a plurality of retaining frames are slidably installed in the slide groove.

[0015] The beneficial effects of the present invention are as follows: a cold-bending forming device for special-shaped steel pipes of the present invention arranges a bending mechanism and a holding mechanism on a workbench. When bending, the rotation of the pipe bending die will drive the clamping block and the square pipe in the clamping space to rotate, thereby bending the square pipe. In the process of the tube bending die rotating, the bending column thereon will be driven to rotate, and the bending column can drive the corresponding retaining frame to rotate around the first direction, and after the bending is completed, multiple retaining frames will be evenly distributed along the axial direction of the square tube on the bending section, that is, multiple retaining mechanisms will be located on the bending section, and because the side surface of the square tube along the second direction close to the tube bending die (the inner side surface of the square tube) and the side surface of the square tube along the second direction close to the clamping block (the outer side surface of the square tube) are both arc surfaces, when the inner side surface of the square tube is bent, the arc-shaped inner side surface can guide the bending force, so that the inner side surface is not easy to wrinkle toward the side close to the central axis of the square tube, and when the outer side surface of the square tube is bent, the outer side surface has a certain margin, and has a certain buffering effect when the outer side surface is bent and stretched, so that the outer side surface is not easy to flatten, thereby reducing the influence on the inner diameter of the square tube after bending, and improving the bending quality of the square tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the overall structure of an embodiment of a cold-bending forming device for a special-shaped steel pipe of the present invention; Figure 2 for Figure 1 The enlarged view of point A in the middle; Figure 3 for Figure 1 The enlarged view of point B in the middle; Figure 4 A top view of the overall structure of an embodiment of a cold-bending forming device for a special-shaped steel pipe of the present invention; Figure 5 for Figure 4 Cross-sectional view at the middle edge CC; Figure 6 for Figure 5 The enlarged view of point D in the middle; Figure 7 It is a schematic diagram of a holding mechanism of an embodiment of a cold-bending forming device for a special-shaped steel pipe of the present invention; Figure 8 It is a schematic diagram of a square tube before and after deformation of an embodiment of a cold-bending forming device for a special-shaped steel tube of the present invention.

[0018] In the figure: 100, square tube; 200, workbench; 210, first driving member; 220, support seat; 230, fourth driving member; 300, bending mechanism; 310, bending tube mold; 311, second driving member; 312, slide groove; 313, limit groove; 320, clamping block; 330, bending column; 331, head end; 332, tail end; 400, holding mechanism; 410, holding frame; 411, matching groove; 412, first frame; 413, second frame; 414, first inclined groove; 415, third driving member; 420, clamping wheel; 500, limit mechanism; 510, driving block; 520, limit block; 521, slot; 530, fifth driving member. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] An embodiment of a cold-bending forming device for a special-shaped steel pipe of the present invention is as follows Figures 1 to 8 shown.

[0021] A cold bending forming device for a special-shaped steel pipe is used to bend a square pipe 100, comprising a workbench 200, a bending mechanism 300 and a plurality of holding mechanisms 400. The bending mechanism 300 comprises a pipe bending die 310 and a clamping block 320. The pipe bending die 310 is mounted on the workbench 200 so as to be rotatable about a first direction, wherein the first direction is a vertical direction. The clamping block 320 is mounted on the pipe bending die 310, and the clamping block 320 can move along a second direction toward a side close to the pipe bending die 310 to close the pipe bending die 310 to close the pipe bending die 310, wherein the second direction is perpendicular to the first direction and the second direction is a horizontal direction. After the close-molding, a clamping space for clamping the square pipe 100 is defined between the clamping block 320 and the pipe bending die 310, wherein in the initial state, the square pipe 100 is arranged along a third direction and a plurality of holding mechanisms 400 are arranged in sequence along the third direction on the pipe bending die 310, wherein the third direction is perpendicular to the first direction and the second direction respectively, and the third direction is a horizontal direction.

[0022] The holding mechanism 400 includes a holding frame 410 and four clamping members. The holding frame 410 is mounted on the tube bending die 310. The four clamping members are mounted on the holding frame 410. The four clamping members are respectively located in four right-angle regions of the square tube 100. Each clamping member can apply a force toward one side of the central axis of the square tube 100 to the right-angle region corresponding to the holding frame 410, and make the four side surfaces of the square tube 100 in the right-angle region in the third direction all become arc surfaces, and the concave side of the arc surface is arranged toward the central axis of the square tube 100. The tube bending die 310 is provided with a bending column 330, which is coaxially arranged with the tube bending die 310. The bent portion of the square tube 100 is called a bending section. The bending column 330 can drive the plurality of holding frames 410 to rotate around the first direction, and make the plurality of holding frames 410 evenly distributed on the bending section along the axis direction of the bending section.

[0023] Specifically, the workbench 200 is provided with a first driving member 210, which is used to drive the tube bending die 310 to rotate around a first direction, and the first driving member 210 is a motor. The tube bending die 310 is provided with a second driving member 311, which can drive the clamping block 320 to move toward or away from the tube bending die 310 along the second direction, and the second driving member 311 is a hydraulic telescopic cylinder.

[0024] Further, three holding mechanisms 400 are provided. Alternatively, more than three holding mechanisms 400 are provided. A support seat 220 is provided on the workbench 200 , and the support seat 220 is coaxially arranged with the clamping space. The square tube 100 is placed on the support seat 220 and can move along the support seat 220 .

[0025] In this embodiment, a bending mechanism 300 and a holding mechanism 400 are arranged on the workbench 200. When in use, the square tube 100 is first clamped in the clamping space, and then the clamping block 320 is driven to move along the second direction to the side close to the tube bending die 310 to close the tube bending die 310, and the clamping member applies a force toward the side of the central axis of the square tube 100 to the right angle area of ​​the square tube 100 corresponding to it, so that the four side surfaces of the square tube 100 in the right angle area in the third direction (in the length direction of the square tube 100) are deformed toward the side away from the central axis of the square tube 100, see the attached Figure 8 As shown, the square tube 100 before deformation is Figure 8 The dotted line indicates that the deformed square tube 100 is Figure 8 That is, the four side surfaces of the square tube 100 are all convex toward the side away from the central axis of the square tube 100 and are in an arc shape.

[0026] For the convenience of explanation, the side surface of the square tube 100 close to the tube bending die 310 along the second direction is called the inner side surface, and the side surface of the square tube 100 close to the clamping block 320 along the second direction is called the outer side surface. Then, the tube bending die 310 is driven to rotate around the first direction, and the rotation of the tube bending die 310 drives the clamping block 320 and the square tube 100 in the clamping space to rotate, thereby bending the square tube 100. In the process of the tube bending die 310 rotating, the bending column 330 thereon will be driven to rotate, and the bending column 330 can drive the corresponding retaining frame 410 to rotate around the first direction. After the bending is completed, multiple retaining frames 410 will be evenly distributed along the axial direction of the square tube 100 on the bending section, that is, multiple retaining mechanisms 400 will be located on the bending section. Since the inner side surface and the outer side surface of the square tube 100 are both arc surfaces, when the inner side surface of the square tube 100 is bent, the arc-shaped inner side surface can guide the bending force, so that the inner side surface is not easy to wrinkle toward the side close to the central axis of the square tube 100. When the outer side surface of the square tube 100 is bent, the outer side surface has a certain margin, and has a certain buffering effect when the outer side surface is bent and stretched, so that the outer side surface is not easy to flatten, thereby reducing the influence on the inner diameter of the square tube 100 after bending, and improving the bending quality of the square tube 100.

[0027] In this embodiment, the bending column 330 has a head end 331 and a tail end 332, and the head end 331 and the tail end 332 are arranged in sequence in the rotation direction of the tube bending die 310. In the rotation direction of the tube bending die 310, the head end 331 is located in front of the tail end 332. Figure 4 The direction shown in the figure is rotated clockwise, and the direction close to the clockwise arrow in the rotation direction is called the front, and the direction away from the clockwise arrow is called the rear. The diameter of the bending column 330 gradually increases from the head end 331 to the tail end 332. Multiple retainers 410 are slidably installed on the bending tube die 310, and each retainer 410 is provided with a matching groove 411, which is slidably matched with the bending column 330. In the initial state, multiple retainers 410 are slidably installed on the head end 331 of the bending column 330. The sizes of the multiple matching grooves 411 are different, and the size of the matching groove 411 close to the head end 331 of the bending column 330 is smaller than the size of the matching groove 411 close to the tail end 332 of the bending column 330, and The size of the matching groove 411 on the side of the tail end 332 of the bending column 330 is smaller than the diameter of the tail end 332 of the bending column 330, and the size of the matching groove 411 on the side close to the head end 331 of the bending column 330 is larger than the diameter of the head end 331 of the bending column 330. Therefore, in the process of the bending column 330 rotating with the bending tube mold 310, when the diameter of the bending column 330 can adapt to the diameter of the matching groove 411, the retaining frame 410 where the matching groove 411 is located can rotate synchronously with the bending column 330 around the first direction.

[0028] Specifically, a slide groove 312 is provided on the tube bending die 310 , the slide groove 312 is coaxially arranged with the tube bending die 310 , and the plurality of retaining frames 410 are slidably installed in the slide groove 312 .

[0029] In this embodiment, the bending column 330 is set to a structure with a gradually changing diameter. When the tube bending die 310 is used, the bending column 330 will also rotate with the tube bending die 310. In the initial state, multiple matching grooves 411 are slidably installed on the side of the head end 331 of the bending column 330. At this time, the bending column 330 and the matching groove 411 cannot be adapted. The bending column 330 will rotate around the first direction relative to the multiple retaining frames 410. At this time, the retaining frame 410 will slide in the slide groove 312. As the tube bending die 310 rotates, the diameter of the bending column 330 passing through the matching groove 411 gradually increases. When it rotates to the point where the diameter of the matching groove 411 can be adapted to the diameter of the bending column 330, the retaining frame 410 corresponding to the matching groove 411 can be driven by the bending column 330 to rotate. Since the diameter of the bending column 330 gradually increases from the head end 331 to the tail end 332, as the bending column 330 rotates relative to the matching groove 411, whenever the diameter of the bending column 330 can match the diameter of a matching groove 411, the bending column 330 will be able to drive the holder 410 where the matching groove 411 is located to rotate. That is, when in use, the bending angle of the square tube 100 is known, and by setting the center angle of the diameter of the bending column 330 that can match the matching groove 411 on the bending die 310, multiple holders 410 can be evenly distributed on the bending section of the square tube 100 after bending. For example, when the bending angle of the square tube 100 is 120° and the holders 410 are set to 3, the angles between the three holders 410 sequentially set on the bending section of the square tube 100 are all 40 degrees.

[0030] In this embodiment, a limiting groove 313 is provided on the tube bending die 310 , and the bent square tube 100 can abut against the limiting groove 313 .

[0031] By setting the limiting groove 313, the inner side surface of the bent square tube 100 will abut against the limiting groove 313. This setting is because after the square tube 100 is bent, under the action of the arc surface of the inner side surface of the square tube 100, the inner side surface of the square tube 100 will tend to move toward the side close to the limiting groove 313. The limiting groove 313 is used to limit the inner side surface of the bent square tube 100, thereby limiting the amount of movement of the inner side surface of the square tube 100 toward the side close to the limiting groove 313.

[0032] In this embodiment, two adjacent retaining frames 410 are connected via a first elastic member, which is a spring. By arranging the first elastic member between the two adjacent retaining frames 410, the retaining frames 410 can be easily reset.

[0033] In this embodiment, the retaining frame 410 includes a first frame body 412 and a second frame body 413. The first frame body 412 is slidably installed on the bending mold 310. The second frame body 413 is connected to the first frame body 412 through a third driving member 415, so that the second frame body 413 can move along the second direction toward or away from the side of the first frame body 412, and when the second frame body 413 moves along the second direction toward the side of the first frame body 412, the second frame body 413 and the first frame body 412 can clamp the square tube 100. The third driving member 415 is a hydraulic telescopic cylinder. Two clamping members are respectively arranged on the first frame body 412 and the second frame body 413, and the two clamping members on the first frame body 412 and the two clamping members on the second frame body 413 are arranged face to face in the second direction.

[0034] In this embodiment, the clamping member is a clamping wheel 420, which is rotatably arranged around a reference axis, and the reference axis is the tangent direction of the right-angle region of the square tube 100 where the clamping wheel 420 is located. The two clamping wheels 420 on the first frame 412 can approach each other along the first direction, and the two clamping wheels 420 on the second frame 413 can approach each other along the first direction.

[0035] Specifically, two first inclined grooves 414 are provided on the first frame 412, and the two first inclined grooves 414 are symmetrically arranged about the central axis of the square tube 100 in the first direction. The two first inclined grooves 414 are arranged one-to-one with the two clamping wheels 420 correspondingly arranged on the first frame 412, and the clamping wheels 420 on the first frame 412 are slidably installed in the corresponding first inclined grooves 414. The two ends of the first inclined groove 414 are respectively referred to as the first end and the second end, the first end is located on the side of the second end close to the square tube 100 in the second direction, and the first end is located on the side of the second end in the first direction away from the central axis of the square tube 100 in the first direction. In the initial state, the clamping wheel 420 on the first frame 412 is located on the first end side of the first inclined groove 414.

[0036] The second frame 413 is provided with two second inclined grooves, which are symmetrically arranged about the central axis of the square tube 100 in the first direction. The two second inclined grooves are arranged one by one corresponding to the two clamping wheels 420 arranged on the second frame 413, and the clamping wheels 420 on the second frame 413 are slidably installed in the corresponding second inclined grooves. The two ends of the second inclined groove are respectively called the third end and the fourth end, and the third end is located on the side of the fourth end close to the square tube 100 in the second direction, and the third end is located on the side of the fourth end in the first direction away from the central axis of the square tube 100 in the first direction. In the initial state, the clamping wheel 420 on the second frame 413 is located on the side of the third end of the second inclined groove.

[0037] In this embodiment, by setting the first frame 412 and the second frame 413, when in use, the third driving member 415 causes the second frame 413 to move along the second direction toward the first frame 412 to clamp the square tube 100, and in the process of the first driving member 210 moving, the two clamping wheels 420 on the first frame 412 and the two clamping wheels 420 on the second frame 413 will gradually apply a force toward the central axis of the square tube 100 to the four right-angled areas of the square tube 100 where they are located, and the first frame 412 and the second frame 413 mutually move in the second direction. During the approaching process, driven by the third driving member 415, the two clamping wheels 420 on the first frame 412 will tend to approach each other in the first direction. Similarly, the two clamping wheels 420 on the second frame 413 will tend to approach each other in the first direction, so that the forces applied by the four clamping wheels 420 to the square tube 100 will tend to the central axis of the square tube 100. Under the action of the four clamping wheels 420, the four side surfaces of the square tube 100 that are in contact with and pressed by the clamping wheels 420 will gradually become arc surfaces, and the concave side of the arc surface is set toward the central axis of the direction. See the attached Figure 8 As shown, the square tube 100 before deformation is Figure 8 The dotted line indicates that the deformed square tube 100 is Figure 8 That is, the four side surfaces of the square tube 100 are all convex toward the side away from the central axis of the square tube 100 and are in an arc shape.

[0038] In this embodiment, a cold-bending forming device for a special-shaped steel pipe also includes a limiting mechanism 500, which includes a driving block 510. The driving block 510 and the clamping block 320 are on the same side of the workbench 200. A fourth driving member 230 is provided on the workbench 200. The driving block 510 is installed on the fourth driving member 230. The fourth driving member 230 can cause the driving block 510 to move along the second direction toward or away from the side of the square tube 100, and the driving block 510 can move along the second direction toward the side close to the square tube 100 and abut against the square tube 100.

[0039] Furthermore, the limiting mechanism 500 further includes a limiting block 520, which is mounted on the driving block 510 and can move synchronously with the driving block 510. A clamping slot 521 is provided on the limiting block 520, and the limiting block 520 moves along the second direction toward the side close to the square tube 100 so that the clamping slot 521 can slide and cooperate with the square tube 100. A fifth driving member 530 is provided on the driving block 510, and the fifth driving member 530 can enable the limiting block 520 to move along the third direction relative to the driving block 510, and both the fourth driving member 230 and the fifth driving member 530 are hydraulic telescopic cylinders.

[0040] In this embodiment, a driving block 510 and a limiting block 520 are provided. When in use, the fourth driving member 230 is used to cause the driving block 510 to move along the second direction toward the side close to the square tube 100. The movement of the driving block 510 will drive the limiting block 520 to move until the limiting groove 313 abuts against the square tube 100. When the square tube 100 is bent, the fifth driving member 530 is started to drive the limiting block 520 to move synchronously with the square tube 100, so that the square tube 100 and the limiting block 520 remain relatively still, thereby preventing the square tube 100 from being scratched.

[0041] In another possible implementation, a cold-bending forming device for a special-shaped steel pipe also includes a control system, a first sensor is arranged on the first frame 412, and the first sensor is used to sense the size of the inner side surface of the square tube 100 in the first direction, and a second sensor is arranged on the second frame 413, and the second sensor is used to sense the size of the outer side surface of the square tube 100 in the first direction. The first sensor and the second sensor are both position sensors. The first sensor and the second sensor are both electrically connected to the control system, and the control system can collect information fed back by the first sensor and the second sensor. The first driving member 210, the second driving member 311, the third driving member 415, the fourth driving member 230 and the fifth driving member 530 are all electrically connected to the control system. The control system can control the first driving member 210, the second driving member 311, the third driving member 415, the fourth driving member 230 and the fifth driving member 530 to start or stop.

[0042] By setting the first sensor and the second sensor, the size of the inner side surface of the square tube 100 in the first direction and the size of the outer side surface of the square tube 100 in the first direction can be sensed during use, and the data obtained through feedback from the control system can be analyzed. If the square tube 100 is flattened, the size of the inner side surface of the square tube 100 in the first direction and the size of the outer side surface of the square tube 100 in the first direction will change. Therefore, adjustments can be made after collecting data to change the relative displacement between the first frame 412 and the second frame 413, thereby improving the bending quality of the square tube 100.

[0043] In combination with the above embodiments, the working process is as follows: When in use, the square tube 100 is first placed on the workbench 200, overlapped on the support seat 220 and passed through the clamping space. Then the second driving member 311, the third driving member 415 and the fourth driving member 230 are activated, so that the second driving member 311 is activated to move the clamping block 320 along the second direction to the side close to or away from the bending die 310 and clamp the square tube 100, the third driving member 415 is activated to move the second frame 413 along the second direction to the side close to the first frame 412 and clamp the square tube 100, and the fourth driving member 230 is activated to move the driving block 510 along the second direction to the side close to the square tube 100, and the movement of the driving block 510 drives the limit block 520 to move until the limit groove 313 abuts against the square tube 100.

[0044] The square tube 100 can be clamped when the second frame 413 is urged to move toward the first frame 412 along the second direction by the third driving member 415, and in the process of the first driving member 210 moving, the two clamping wheels 420 on the first frame 412 and the two clamping wheels 420 on the second frame 413 will gradually apply a force toward the central axis of the square tube 100 to the four right-angled areas of the square tube 100 where they are located, and in the process of the first frame 412 and the second frame 413 approaching each other in the second direction, the third driving member 4 15, the two clamping wheels 420 on the first frame 412 will tend to approach each other in the first direction. Similarly, the two clamping wheels 420 on the second frame 413 will tend to approach each other in the first direction, so that the forces applied by the four clamping wheels 420 to the square tube 100 will tend to the central axis of the square tube 100. Under the action of the four clamping wheels 420, the four side surfaces of the square tube 100 that are in contact with and pressed by the clamping wheels 420 will gradually become arc surfaces, and the concave side of the arc surface is set toward the central axis of the direction. See the attached Figure 8 As shown, the square tube 100 before deformation is Figure 8 The dotted line indicates that the deformed square tube 100 is Figure 8 That is, the four side surfaces of the square tube 100 are all convex toward the side away from the central axis of the square tube 100 and are in an arc shape.

[0045] Then, the first driving member 210 is started to drive the tube bending die 310 to rotate in the first direction. The rotation of the tube bending die 310 drives the clamping block 320 and the square tube 100 in the clamping space to rotate, and the square tube 100 is bent. When the square tube 100 is bent, the fifth driving member 530 is started to drive the limit block 520 to move synchronously with the square tube 100, so that the square tube 100 and the limit block 520 remain relatively still to prevent the square tube 100 from being scratched.

[0046] And when the tube bending die 310 rotates, the bending column 330 will also rotate with the tube bending die 310. Since in the initial state, multiple matching grooves 411 are slidably installed on the side of the head end 331 of the bending column 330, the bending column 330 and the matching groove 411 cannot be adapted at this time, and the bending column 330 will rotate around the first direction relative to the multiple retaining frames 410. At this time, the retaining frame 410 will slide in the slide groove 312. As the tube bending die 310 rotates, the diameter of the bending column 330 passing through the matching groove 411 gradually increases. When it rotates to the point where the diameter of the matching groove 411 can be adapted to the diameter of the bending column 330, the retaining frame 410 corresponding to the matching groove 411 can be driven by the bending column 330 to rotate.

[0047] Since the diameter of the bending column 330 gradually increases from the head end 331 to the tail end 332, as the bending column 330 rotates relative to the matching groove 411, whenever the diameter of the bending column 330 can match the diameter of a matching groove 411, the bending column 330 will be able to drive the holder 410 where the matching groove 411 is located to rotate. That is, when in use, the bending angle of the square tube 100 is known, and by setting the center angle of the diameter of the bending column 330 that can match the matching groove 411 on the bending die 310, multiple holders 410 can be evenly distributed on the bending section of the square tube 100 after bending. That is, the plurality of holding mechanisms 400 will all be located on the bending section, and since the inner side surface of the square tube 100 is an arc surface, when the inner side surface of the square tube 100 is bent, the arc-shaped inner side surface can guide the bending force, so that the inner side surface is not easy to generate wrinkles toward the side close to the central axis of the square tube 100; when the outer side surface of the square tube 100 is bent, the outer side surface has a certain margin, and has a certain buffering effect when the outer side surface is bent and stretched, so that the outer side surface is not easy to flatten, thereby reducing the influence on the inner diameter of the square tube 100 after bending, and improving the bending quality of the square tube 100.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A cold bending forming equipment for special-shaped steel pipes, used for bending square pipes, characterized by: It includes a workbench, a bending mechanism and multiple holding mechanisms; the bending mechanism includes a tube bending die and a clamping block, the tube bending die can be installed on the workbench so as to rotate around a first direction, the first direction is a vertical direction; the clamping block is installed on the tube bending die, the clamping block can move along a second direction to a side close to the tube bending die to close the tube bending die with the tube bending die, the second direction is perpendicular to the first direction, and the second direction is a horizontal direction; a clamping space for clamping a square tube is defined between the clamping block and the tube bending die after closing the mold, in an initial state, the lower tube is arranged along a third direction and multiple holding mechanisms are arranged in sequence on the tube bending die along the third direction, the third direction is perpendicular to the first direction and the second direction respectively, the third direction is a horizontal direction, and the holding mechanism includes a holding mechanism. A holder and four clamping members, the holder is installed on the tube bending die, and the four clamping members are all installed on the holder, and the four clamping members are respectively located in four right-angle areas of the square tube, and each clamping member can apply a force toward one side of the central axis of the square tube to the right-angle area corresponding to it, and make the four side surfaces of the square tube in the right-angle area in the third direction become arc surfaces, and the concave side of the arc surface is arranged toward the central axis of the square tube; a bending column is arranged on the tube bending die, and the bending column is coaxially arranged with the tube bending die, and the bent part of the square tube is called a bending section, and the bending column can drive multiple holders to rotate around the first direction, and make the multiple holders evenly distributed on the bending section along the axial direction of the bending section.

2. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: The bending column has a head end and a tail end, which are arranged in sequence in the rotation direction of the bending die. In the rotation direction of the bending die, the head end is located in front of the tail end; and the diameter of the bending column gradually increases from the head end to the tail end; multiple retaining frames are slidably installed on the bending die, and each retaining frame is provided with a matching groove, which is slidably matched with the bending column. In the initial state, multiple retaining frames are slidably installed on the head end side of the bending column, and the sizes of the multiple matching grooves are different, and the size of the matching groove close to the head end of the bending column is smaller than the size of the matching groove close to the tail end of the bending column. Therefore, in the process of the bending column rotating with the bending die, when the diameter of the bending column can adapt to the diameter of the matching groove, the retaining frame where the matching groove is located can rotate synchronously with the bending column around the first direction.

3. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: Two adjacent retaining frames are connected via a first elastic member.

4. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: The retaining frame includes a first frame body and a second frame body. The first frame body is slidably installed on the tube bending mold. The second frame body is connected to the first frame body, and the second frame body can move toward or away from one side of the first frame body along the second direction. Two clamping members are respectively arranged on the first frame body and the second frame body, and the two clamping members on the first frame body and the two clamping members on the second frame body are arranged face to face in the second direction.

5. The cold-bending forming equipment for special-shaped steel pipes according to claim 4, characterized in that: The clamping member is a clamping wheel, which can be rotatably arranged around a reference axis, and the reference axis is the tangent direction of the right-angle area of ​​the square tube where the clamping wheel is located; and the two clamping wheels on the first frame can approach each other along the first direction, and the two clamping wheels on the second frame can approach each other along the first direction.

6. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: It also includes a limiting mechanism, which includes a driving block. The driving block can move toward or away from one side of the square tube along the second direction, and the driving block can abut against the square tube when it moves toward one side of the square tube along the second direction.

7. The cold-bending forming equipment for special-shaped steel pipes according to claim 6, characterized in that: The limiting mechanism also includes a limiting block, which is installed on the driving block and can move synchronously with the driving block. A slot is provided on the limiting block. When the limiting block moves along the second direction toward the side close to the square tube, the slot can slide with the square tube. The limiting block can move along the third direction relative to the driving block.

8. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: A limiting groove is provided on the tube bending die, and the bent square tube can abut against the limiting groove.

9. The cold-bending forming equipment for special-shaped steel pipes according to claim 1, characterized in that: There are three holding mechanisms.

10. The cold-bending forming equipment for special-shaped steel pipes according to claim 2, characterized in that: A slide groove is provided on the tube bending die, the slide groove is coaxially arranged with the tube bending die, and a plurality of retaining frames are slidably installed in the slide groove.

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