Push bending die and pipe bending machine

Abstract

The application discloses a push-bending die and a pipe bending machine. The push-bending die is used for forming a bent pipe and comprises an outer forming die membrane, a linear driving unit, an inner forming die membrane and a pressing block. The outer forming die membrane is of a split structure and comprises at least two sliding blocks. Each sliding block is driven by a corresponding linear driving unit to be combined or separated with each other. A cavity is formed in the combined outer forming die membrane, and the cavity is matched with the outer wall contour of the bent pipe. The inner forming die membrane is of a split structure and comprises at least two inner cores. The outer wall of the combined inner forming die membrane is matched with the inner wall contour of the bent pipe, and the inner forming die membrane is provided with a wedge groove in the closing direction. The pressing block is arranged on the sliding block facing the wedge groove, and the pressing block is wedged into the wedge groove in the combined state. The application has the beneficial effect that the relative displacement and deformation of the split inner forming die membrane caused by the lateral bending force during the push-bending process are eliminated.

Description

Technical Field

[0001] This invention relates to the field of pipe bending technology, and more particularly to push-bending molds and pipe bending machines. Background Technology

[0002] Currently, metal pipe bending is mainly accomplished using specialized pipe bending machines. These machines have become indispensable specialized equipment in the pipe bending field, widely used in industries such as automotive, power construction, bridges, and shipbuilding that require pipe bending. However, existing pipe bending machines have the following shortcomings: First, they are expensive to manufacture and sell, with high-end CNC pipe bending machines costing hundreds of thousands to millions of yuan. Second, they are single-function specialized equipment, with no other uses besides pipe bending, resulting in low equipment utilization and increased production costs. Furthermore, existing pipe bending machines also suffer from unstable bending quality and difficulty in guaranteeing forming accuracy. Therefore, it is necessary to seek a technical solution that can process bent pipes without the need for specialized bending equipment, in order to reduce production costs and improve equipment versatility.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] The technical problem to be solved by this invention is to address the issues of limited functionality and unstable bending quality in existing pipe bending machines.

[0005] The present invention solves the above-mentioned technical problems through the following technical means: This invention claims protection for a push-bending die used to form bent pipe parts. The push-bending die includes an outer forming die, a linear drive unit, an inner forming die, and a clamping block. The outer forming die has a split structure, including at least two sliders. Each slider is driven by a corresponding linear drive unit to join or separate with each other. The joined outer forming die has a cavity that matches the outer wall contour of the bent pipe part. The inner forming membrane has a split structure, including at least two inner cores. The outer wall of the assembled inner forming membrane is adapted to the contour of the inner wall of the bent pipe. The inner forming membrane has a wedge groove along the mold closing direction. A clamping block is provided on the slider facing the wedge groove. In the assembled state, the clamping block is wedged into the wedge groove.

[0006] Preferably, it also includes a lower plate and a support plate. There are two support plates, which are symmetrically placed on the lower plate. The lower plate and the support plates together enclose a first space. Two sliders are symmetrically arranged in the first space. The two sliders are connected to linear drive units set on the corresponding support plates.

[0007] The fixing of the support plate is not limited to the first bolt; it can also be done by welding or other methods.

[0008] Preferably, the surfaces of the two opposing sliders have corresponding forming grooves, the cross-section of the forming grooves is L-shaped, and the corners are rounded; when the two sliders are joined together, the two forming grooves are joined to form a cavity.

[0009] Preferably, there are two inner cores placed at the top and bottom of the cavity. Both inner cores are half-circular cylindrical structures. The inner core at the bottom is the second inner core, and the inner core at the top is the first inner core. A second groove is opened radially on one side of the second inner core. The top of the second groove is closed and the bottom of the second groove is open, so that the first inner core and the second inner core after being assembled form a wedge groove along the mold closing direction. The bottom of the second inner core extends outward from the cavity. The second inner core located outside the cavity is fixed to the lower plate by a second column.

[0010] Preferably, it also includes a third cylinder, the upper inner core is a first inner core, the bottom end of the first inner core extends outward from the cavity, the first inner core located outside the cavity is provided with a first column, and the first column is connected to the third cylinder mounted on the lower plate.

[0011] The first inner core is located at the top and is a half-circular cylindrical structure.

[0012] Preferably, a limiting block is provided on the lower plate. The limiting block has an inverted U-shaped structure and is in clearance fit with the through hole penetrating the side of the first column to limit the movement distance of the first inner core driven by the third cylinder.

[0013] Preferably, reinforcing ribs are provided between the surfaces of the two opposing support plates and the corresponding positions of the lower plate.

[0014] To ensure the stability of the support plates, reinforcing ribs are installed between the surfaces of the two opposing support plates and the corresponding positions of the lower plate.

[0015] The present invention also claims protection for a pipe bending machine, including a bending die, an upper plate, a guide structure, a mandrel, and a drive mechanism. The upper plate is provided directly above the lower plate, and a guide structure is provided between the upper plate and the lower plate in a vertical direction. The top of the upper plate is connected to the drive mechanism. When at least two sliders are assembled, a mandrel is provided at the bottom of the upper plate located directly above the top of the cavity.

[0016] The preferred drive mechanism is a 63T hydraulic press. It is assembled with a general-purpose 63T hydraulic press through a bending die to convert the general-purpose 63T hydraulic press into a pipe bending forming device. The pipe bending function is integrated into the general-purpose hydraulic press in the form of a die, eliminating the need to purchase a dedicated pipe bending machine. This not only retains the original multiple processing capabilities of the hydraulic press, but also achieves efficient forming of pipe bending parts, overcoming the shortcomings of traditional pipe bending machines, such as single function and low equipment utilization.

[0017] Preferably, it also includes a first guide post, and a first guide hole is provided on the top of both support plates. The axis of the first guide hole is vertical, and the first guide post provided at the bottom of the upper plate and the first guide hole at the top of the support plate form a sliding guide fit.

[0018] It is not limited to the combination of guide sleeve and guide post, but can also be a sliding guide structure such as guide rail. It is mainly used to guide when relative sliding occurs between the lower plates.

[0019] Preferably, it also includes insert blades. There are two insert blades, which are placed on both sides of the bottom of the upper plate. When at least two sliders are joined together, the insert blades are inserted into the gap formed between the corresponding support plate and the slider. The side of the insert blades is provided with a clearance groove for avoiding the linear drive unit.

[0020] The advantages of this invention are: 1. A split-type outer forming die, driven by a corresponding cylinder, moves and assembles to form a cavity. The cavity matches the outer contour of the bent pipe. This is then combined with a split-type inner forming die, which matches the inner contour of the bent pipe. When the mandrel is pressed down, this ensures full support for the inner and outer walls of the pipe to be formed during bending, preventing wall collapse. It also provides space for subsequent demolding. The split-type inner forming die, after assembly, forms a wedge groove. This wedge groove, together with the clamping block, forms a wedge-shaped tension fit, eliminating relative displacement and deformation of the split-type inner forming die due to lateral bending forces during the bending process.

[0021] 2. Furthermore, by setting the first inner core as a lifting movable component that can be driven by a cylinder, an axial clearance space is generated between the bent tube and the inner forming diaphragm, avoiding the problem of traditional integral mandrels being difficult to remove due to the springback of the bent tube, thus realizing quick manual removal of parts and significantly improving production efficiency.

[0022] 3. Furthermore, the insert is designed to prevent the two sliders from being stretched apart, and together with the clamping block, it prevents the first inner core and the second inner core from being misaligned. The two act on different objects, but together they achieve double locking of the push-bending mold.

[0023] 4. Through the coordinated action of the split internal forming mold, the split external forming mold, the wedge reinforcement, the insert cutter and the cylinder demolding, the overall structure is not only compact and the components do not interfere with each other during operation, but also the bending of pipe parts can be completed with high precision and high efficiency on a regular hydraulic press. Attached Figure Description Figure 1 This is a schematic diagram of the pipe bending machine in an embodiment of the present invention; Figure 2 This is a top view of the pipe bending machine in an embodiment of the present invention; Figure 3 yes Figure 2 A cross-sectional diagram from a BB perspective; Figure 4 yes Figure 2 A cross-sectional diagram from the AA perspective; Figure 5 This is a schematic diagram of the structure of the pipe bending machine removing the first and second sliders in an embodiment of the present invention; Figure 6 This is a schematic diagram of the structure of the bending die in this embodiment of the invention, showing the removal of the second support plate, the first support plate, and the bent pipe component. 100. Lower plate; 101. First support plate; 1010. Reinforcing rib; 102. Second support plate; 103. First slider; 104. Second slider; 105. First cylinder; 106. Second cylinder; 107. First inner core; 1070. First column; 1071. Limiting block; 108. Second inner core; 1080. Second column; 1081. Second slide groove; 109. Third cylinder; 110. Clamping block; 20. Upper plate; 30. First guide post; 40. Second guide sleeve; 50. Second guide post; 60. First insert; 600. First clearance groove; 70. Second insert; 700. Second clearance groove; 80. Mandrel; a. Pipe bending fittings. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] See Figure 1 and Figure 2 This embodiment requires protection of a pipe bending machine for forming a bent pipe component a, which includes a straight pipe section and a bent section. The pipe bending machine includes a bending die, an upper plate 20, a first guide post 30, a second guide sleeve 40, a second guide post 50, a first inserter 60, a second inserter 70, a mandrel 80, and a drive mechanism (not shown in the figure).

[0026] The bending die includes a lower plate 100, a first support plate 101, a second support plate 102, a first slider 103, a second slider 104, a first cylinder 105, a second cylinder 106, a first inner core 107, a second inner core 108, a third cylinder 109, and a clamping block 110.

[0027] The lower plate 100 is the mounting base of the entire bending die. A three-dimensional coordinate system is established with the center of the upper surface of the lower plate 100 as the origin, the long side of the lower plate 100 as the x-axis, the wide side of the lower plate 100 as the y-axis, and the height of the lower plate 100 as the z-axis.

[0028] The lower plate 100 has a first support plate 101 and a second support plate 102 arranged symmetrically along the y-axis, and they are fixedly connected by a first bolt. A first gap is reserved between the first support plate 101 and the second support plate 102. The first support plate 101, the second support plate 102 and the lower plate 100 enclose a first space.

[0029] It is worth mentioning that the fixing of the support plate is not limited to the first bolt, but can also be done by welding or other methods. In order to ensure the stability of the support plate, reinforcing ribs 1010 are provided between the surfaces of the two opposing support plates and the corresponding positions of the lower plate 100.

[0030] A first slider 103 and a second slider 104 are symmetrically arranged along the y-axis in the first space and are connected by a fourth bolt. The surfaces of the opposing first slider 103 and second slider 104 are each provided with a forming groove. The cross-section of the forming groove on the yz plane is L-shaped, and the corners are rounded.

[0031] An upper plate 20 is provided directly above the lower plate 100. A first guide hole is provided on the top of the support plate. The axis of the first guide hole is vertical. The first guide hole and the first guide post 30 provided at the bottom of the upper plate 20 form a sliding guide fit along the z-axis.

[0032] The second guide sleeve 40 is installed on the lower plate 100 by the second bolt. The axis of the second guide sleeve 40 is vertical. The second guide sleeve 40 and the second guide post 50 set at the bottom of the upper plate 20 form a sliding guide fit along the z-axis.

[0033] It is worth mentioning that the combination of guide sleeve and guide post is not limited to the use of guide rails or other sliding guide structures. It is mainly used to guide the relative sliding between the lower plate 100 and the upper plate 20. When the guide sleeve and guide post are used, it is not limited to the lower plate 100 being equipped with a guide sleeve. The lower plate 100 can also be equipped with a guide post, and the upper plate 20 can be equipped with a corresponding guide sleeve.

[0034] Preferably, there are two sliding guide structures, which are symmetrically arranged along the y-axis and move upward along the y-axis. The sliding guide structures are offset from the positions of the first support plate 101 and the second support plate 102.

[0035] See Figure 3The top of the upper plate 20 is connected to the drive mechanism. The drive mechanism is preferably a 63T hydraulic press. A first inserter 60 and a second inserter 70 are symmetrically arranged along the y-axis at the bottom of the upper plate 20 and are fixed by a third bolt. The first inserter 60 and the second inserter 70 are located directly above the first space, and a second gap is reserved between them. The first inserter 60, the second inserter 70, and the upper plate 20 together form the second space. When the second slider 104 and the first slider 103 are assembled to form an outer molding film, and the second guide post 50 and the second guide sleeve 40 are engaged to their minimum limit positions, the first inserter 60 is inserted into the gap between the first support plate 101 and the first slider 103, and the second inserter 70 is inserted into the gap between the second support plate 102 and the second slider 104. When the second guide post 50 and the second guide sleeve 40 are engaged to their maximum limit positions, the first inserter 60 and the second inserter 70 disengage from their respective gaps.

[0036] The first insert 60 has a first clearance groove 600 penetrating through its side, and the second insert 70 has a second clearance groove 700 penetrating through its side. The groove depths of the second clearance groove 700 and the first clearance groove 600 are parallel to the x-axis direction. Both ends of the second clearance groove 700 and the first clearance groove 600 are open and their groove lengths are parallel to the z-axis.

[0037] A first cylinder 105 is mounted on the first support plate 101. The piston rod of the first cylinder 105, passing through the first clearance groove 600, is connected to the first slider 103 to drive the first slider 103 to move along the x-axis in the first space. A second cylinder 106 is mounted on the second support plate 102. The piston rod of the second cylinder 106, passing through the second clearance groove 700, is connected to the second slider 104 to drive the second slider 104 to move along the x-axis in the second space. When the first slider 103 and the second slider 104 move to the bottom of the second space, the two forming grooves align with each other to form a cavity.

[0038] It is worth mentioning that the design is not limited to cylinders; linear drive units such as ball screws can also be used. The second slider 104 and the first slider 103 are assembled to form an outer forming mold, the internal cavity of which matches the outer contour of the bent pipe a. Furthermore, the number of sliders is not limited to two; it can also be three. The assembly and dispersal of the sliders can be achieved by increasing the corresponding number of cylinders.

[0039] See Figure 4 and Figure 5 and Figure 6The cavity contains a first inner core 107 and a second inner core 108. The second inner core 108 is located at the bottom and has a half-circular cylindrical structure. A second groove 1081 is radially opened on one side of the second inner core 108. The top of the second groove 1081 is closed and the bottom of the second groove 1081 is open, so that the second inner core 108 and the first inner core 107 are joined together to form a wedge groove along the mold closing direction. The bottom of the second inner core 108 extends outward from the cavity. The second inner core 108 located outside the cavity is fixed to the lower plate 100 by a second column 1080.

[0040] The first inner core 107 is located at the top and has a half-circular cylindrical structure. The first inner core 107 and the second inner core 108 are assembled to form an inner molding film, and the outer contour of the inner molding film matches the inner contour of the curved section. The bottom end of the first inner core 107 extends outward from the cavity. The first inner core 107 located outside the cavity is provided with a first column 1070, which is connected to a third cylinder 109 mounted on the lower plate 100. A limit block 1071 is provided on the lower plate 100. The limit block 1071 has an inverted U-shaped structure, and the limit block 1071 is in clearance fit with the through hole penetrating the side of the first column 1070 to limit the movement distance of the first inner core 107 driven by the third cylinder 109.

[0041] It is worth mentioning that the inner core is not limited to two, but can also be three. When there are three, the inner core is a one-third circular arc cylindrical structure.

[0042] The clamping block 110 is elongated and parallel to the x-axis. One end of the clamping block 110 is wedged into the wedge groove, and the other end of the clamping block 110 is connected to the second slider 104 by the fifth bolt.

[0043] The top plate 20, located directly above the top of the cavity, is connected to the mandrel 80 via a sixth bolt. The mandrel 80 fits into the inner wall of the bent tube to be formed. When the second guide post 50 and the second guide sleeve 40 are engaged to their minimum limit positions, the mandrel 80 is inserted into the cavity.

[0044] The process by which this pipe bending machine is used to form pipe bending component a is as follows: S1. Start the first cylinder 105 and the second cylinder 106, so that the first slider 103 and the second slider 104 move in the first space to fit together to form an outer molding film. The outer molding film is placed directly below the second space. At this time, the molding grooves on the first slider 103 and the second slider 104 fit together to form a cavity.

[0045] S2. Place the bent tube to be formed into the cavity from the top, start the third cylinder 109, and drive the first inner core 107 to move up to join with the second inner core 108 to form an inner forming film. The outer contour of the inner forming film matches the inner contour of the bent tube a. At this time, the clamping block 110 is inserted into the wedge groove.

[0046] S3. Start the 63T hydraulic press, which drives the upper plate 20 to move down. The first inserter 60 is inserted into the gap between the first support plate 101 and the first slider 103, and the second inserter 70 is inserted into the gap between the second support plate 102 and the second slider 104 to prevent the corresponding slider from moving backward.

[0047] S4. One end of the clamping block 110 is embedded in the wedge groove. The upper plate 20 drives the mandrel 80 to move downward and act on the bent tube to be formed. As it continues to move downward, the mandrel 80 drives the outer wall of the bent tube to be formed to slide along the cavity. The inner wall of the bent tube to be formed slides along the outer contour of the inner forming mold, thus obtaining the bent tube part a.

[0048] S5. After the bending is completed, drive the 63T hydraulic press to move upward. The first inserter 60 and the second inserter 70 are removed from the first space. The first cylinder 105 and the second cylinder 106 drive the corresponding sliders to reset. The second slider 104 drives the clamping block 110 to return to its original position. Drive the third cylinder 109 to move the first inner core 107 down to its original position. The bent pipe part a is manually taken out along the second inner core 108 to complete the production.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bending die for forming bent pipe parts (a), characterized in that, The bending die includes an outer forming die, a linear drive unit, an inner forming die, and a clamping block (110); the outer forming die has a split structure, including at least two sliders, each slider being driven by a corresponding linear drive unit to join or separate from each other, and a cavity is formed inside the joined outer forming die, the cavity being adapted to the outer wall contour of the bent pipe (a); The inner forming membrane is a split structure, including at least two inner cores. The outer wall of the assembled inner forming membrane is adapted to the inner wall contour of the bent pipe (a). The inner forming membrane has a wedge groove along the mold closing direction. A clamping block (110) is provided on the slider facing the wedge groove. In the assembled state, the clamping block (110) is wedged into the wedge groove.

2. The push-bending die according to claim 1, characterized in that, It also includes a lower plate (100) and a support plate. There are two support plates, which are symmetrically placed on the lower plate (100). The lower plate (100) and the support plates together enclose a first space. Two sliders are symmetrically arranged in the first space. The two sliders are connected to the linear drive units set on the corresponding support plates.

3. The push-bending die according to claim 1 or 2, characterized in that, The surfaces of the two opposing sliders have corresponding forming grooves, the cross-section of which is L-shaped and the corners are rounded; when the two sliders are joined together, the two forming grooves are aligned to form a cavity.

4. The push-bending die according to claim 1 or 2, characterized in that, The cavity contains two inner cores, one above the other. Both inner cores are half-circular cylindrical structures. The lower inner core is the second inner core (108), and the upper inner core is the first inner core (107). A second groove (1081) is radially opened on one side of the second inner core (108). The top of the second groove (1081) is closed and the bottom of the second groove (1081) is open, so that the first inner core (107) and the second inner core (108) after assembly form a wedge groove along the mold closing direction. The bottom of the second inner core (108) extends out of the cavity. The second inner core (108) located outside the cavity is fixed to the lower plate (100) by the second column (1080).

5. The push-bending die according to claim 4, characterized in that, It also includes a third cylinder (109), and the inner core located above is the first inner core (107). The bottom end of the first inner core (107) extends outward from the cavity. The first inner core (107) located outside the cavity is provided with a first column (1070). The first column (1070) is connected to the third cylinder (109) installed on the lower plate (100).

6. The push-bending die according to claim 5, characterized in that, A limiting block (1071) is provided on the lower plate (100). The limiting block (1071) has an inverted U-shaped structure. The limiting block (1071) is in clearance fit with the through hole through the side of the first column (1070) to limit the movement distance of the first inner core (107) driven by the third cylinder (109).

7. The push-bending die according to claim 2, characterized in that, Reinforcing ribs (1010) are provided between the surfaces of the two opposing support plates and the corresponding positions of the lower plate (100).

8. A pipe bending machine, employing the bending die as described in any one of claims 2 to 7, characterized in that, It includes a bending die, an upper plate (20), a guide structure, a mandrel (80) and a drive mechanism. The upper plate (20) is located directly above the lower plate (100). A guide structure is provided between the upper plate (20) and the lower plate (100) to guide vertically. The top of the upper plate (20) is connected to the drive mechanism. When at least two sliders are assembled, the mandrel (80) is located at the bottom of the upper plate (20) directly above the top of the cavity.

9. The pipe bending machine according to claim 8, characterized in that, It also includes a first guide post (30), and a first guide hole is provided on the top of both support plates. The axis of the first guide hole is vertical. The first guide post (30) provided at the bottom of the upper plate (20) and the first guide hole at the top of the support plate form a sliding guide fit.

10. The pipe bending machine according to claim 8, characterized in that, It also includes insert blades. There are two insert blades, which are placed on both sides of the bottom of the upper plate (20). When at least two sliders are joined together, the insert blades are inserted into the gap formed between the corresponding support plate and the slider. The side of the insert blades is provided with a clearance groove for avoiding the linear drive unit.

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