A continuously adjustable reducer device and method of continuously forming a pipe

Abstract

A continuously adjustable reducing pipe device and a pipe continuously forming method, comprising a first roller and a second roller connected with a driving mechanism, the first roller is located directly above the second roller, a first cavity is arranged on the sidewall of the first roller along the circumferential direction, a second cavity is arranged on the sidewall of the second roller, the first roller is rotatably arranged on an axle seat, the axle seat is connected with a lifting driving mechanism through a displacement control rod, the first roller can move vertically, a pipe blank cross section perimeter can be changed by rotating between the first roller and the second roller, a set of roller groups can produce pipe blanks with different perimeter change amounts, the space occupied is small, and the control is convenient, the two sides of the first cavity are fixedly provided with connecting parts, the connecting parts are arranged along the circumferential direction of the first roller, the connecting parts are inserted into the second cavity, when the first roller changes position, the effective connection between the first cavity and the second cavity can be ensured without gap, so as to realize the continuous forming of different pipe diameters / pipe shapes.

Description

Technical Field

[0001] This invention relates to the field of plastic forming technology, and in particular to a continuously adjustable tube shrinking device and a method for continuous tube forming. Background Technology

[0002] Integral molding of variable cross-section irregular pipe fittings has advantages such as low cost, light weight, and superior mechanical properties, and has a wide range of applications in many industries, especially in the manufacturing fields of automobiles, aviation and mobile equipment. The application of irregular pipe fittings largely determines the performance of the overall equipment. The traditional processing methods for variable cross-section irregular pipe fittings are generally divided into two types: one is to form the required pipe fittings in sections and then assemble and weld them together, and the other is the radial pressure bulging process.

[0003] Because spliced ​​parts are difficult to meet the expected requirements in terms of mechanical strength, dimensions, performance, and appearance, and the diameter expansion forming process has difficulty controlling the distribution of pipe diameter expansion, the production of pipe fittings is limited. In order to solve the defects of traditional processing methods, a pipe fitting roll forming method has emerged (such as publication number CN114653769B), which uses forming roller sets to continuously form the pipe blank without applying internal pressure, thus reducing production costs.

[0004] However, the existing pipe roll forming method uses a complex overall structure of equipment. For example, when continuously forming pipes with large deformation, multiple sets of forming rollers are required, which not only increases the cost of use but also increases the production space occupied. Furthermore, it is inconvenient to use, and the staff needs to adjust the forming rollers at different positions in advance so that the forming space between two rollers in the same group meets the dimensional requirements, which greatly increases the labor intensity. Summary of the Invention

[0005] To address the technical problems of inconvenient use, large space occupation, and high cost of existing pipe roll forming methods mentioned above, this invention provides a continuously adjustable tube shrinking device and a continuous pipe forming method.

[0006] The technical solution of this invention is as follows:

[0007] This invention provides a continuously adjustable tube shrinking device, including a first roller and a second roller connected to a drive mechanism. The first roller is located directly above the second roller. A first cavity is provided circumferentially on the side wall of the first roller, and a second cavity is provided on the side wall of the second roller. The first roller is rotatably mounted on a bearing seat, which is connected to a lifting drive mechanism via a displacement control rod. The second roller is rotatably mounted on a base. The first roller can move vertically. The rotation between the first and second rollers can change the perimeter of the tube blank cross-section, thereby continuously reducing the tube blank at different axial positions. The cross-sectional perimeter is used to obtain pre-formed tubes with varying diameters at different locations. A single set of rollers can produce tube blanks with different perimeter variations, occupying little space and being easy to control. It eliminates the need to pre-deploy several roller sets, making it convenient to use and reducing production costs. Connecting parts are fixed on both sides of the first cavity, and the connecting parts are arranged circumferentially along the first roller. The connecting parts are inserted into the second cavity. When the first roller moves vertically to change position, it can ensure an effective connection between the first cavity and the second cavity without any gaps, effectively extruding the tube blank to achieve continuous forming of different tube diameters / shapes.

[0008] Preferably, the first cavity includes a first arc segment, and the connecting portion includes a first straight segment and a transition segment. The first straight segment is located outside the connecting portion and is perpendicular to the side wall of the first roller. The transition segment is located inside the connecting portion and is connected to the first arc segment.

[0009] Preferably, the outline of the second cavity includes a second arc segment and a second straight segment. The second straight segment is located at both ends of the second arc segment and is tangent to the second arc segment. The first straight segment and the second straight segment are in clearance fit, which facilitates the connection between the first cavity and the second cavity and avoids gaps between the first cavity and the second cavity when the first roller moves vertically.

[0010] Preferably, the length of the first straight segment is not greater than the length of the second straight segment to avoid contact between the connecting part and the second arc segment, thus ensuring the roll extrusion quality of the tube blank's arc surface.

[0011] Preferably, the transition section has an angle with the first straight section, which facilitates the transition and forming of the tube blank between the first arc section and the second arc section.

[0012] Preferably, the lengths of the first and second arc segments are both less than half the circumference of the tube blank, and the lengths of the first and second arc segments are both not less than 2 / 5 of the circumference of the tube blank. This ensures the effectiveness of the tube shrinking process and the fit with the tube blank, guarantees the rolling extrusion quality of the tube blank during continuous forming, and avoids the occurrence of wrinkling.

[0013] Preferably, the maximum perimeter of the cross-section of the space enclosed by the first cavity, the second cavity, and the connecting part is greater than the perimeter of the tube blank, and the minimum perimeter is less than the perimeter of the tube blank, which facilitates the placement of the tube blank and can play the role of tube shrinking.

[0014] Preferably, the distance between the two first straight segments is not less than the diameter of the tube blank and not greater than the distance between the two second straight segments, which facilitates the placement of the tube blank and the fit between the first and second straight segments.

[0015] The present invention also provides a method for continuous forming of pipe fittings, as follows:

[0016] Adjust the distance between the first roller and the second roller so that the ends of the first straight segment and the second straight segment are in contact, and place the tube blank between the first cavity and the second cavity;

[0017] Start the drive mechanism to extrude the tube blank into shape using the rollers;

[0018] When tube shrinking is required, the displacement control rod controls the shaft seat to move downward, reducing the distance between the first cavity and the second cavity. After tube shrinking is completed, the displacement control rod controls the shaft seat to rise.

[0019] As can be seen from the above technical solutions, the advantages of the present invention are:

[0020] 1. The first roller can move vertically. The rotation between the first roller and the second roller can change the perimeter of the tube blank cross section, thereby continuously reducing the perimeter of the tube blank at different axial positions to obtain pre-formed tubes with different diameters at various locations. One set of rollers can produce tube blanks with different perimeter variations, occupying little space and being easy to control. There is no need to pre-deploy several roller sets, which is convenient to use and reduces production costs. The connection part can ensure an effective connection between the first cavity and the second cavity without gaps when the first roller moves vertically to change position, effectively extruding the tube blank to achieve continuous forming of different tube diameters / shapes.

[0021] 2. The length of the first straight segment is not greater than the length of the second straight segment to avoid contact between the connecting part and the second arc segment, thus ensuring the quality of the roll extrusion of the tube blank's arc surface.

[0022] 3. The lengths of the first and second arc segments are both less than half the circumference of the tube blank, and the lengths of the first and second arc segments are not less than 2 / 5 of the circumference of the tube blank. This ensures the effectiveness of the tube shrinking process and the fit with the tube blank, guarantees the rolling extrusion quality of the tube blank during continuous forming, and avoids the occurrence of wrinkling.

[0023] 4. The maximum perimeter of the space enclosed by the first cavity, the second cavity, and the connecting part is greater than the perimeter of the tube blank, and the minimum perimeter is less than the perimeter of the tube blank, which facilitates the placement of the tube blank and can play the role of tube shrinking. Attached Figure Description

[0024] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a cross-sectional structural schematic diagram of the continuously adjustable tube shrinking device according to one or more embodiments of the present invention (lifting drive mechanism not shown);

[0026] Figure 2 This is a cross-sectional structural schematic diagram of a roller assembly according to one or more embodiments of the present invention;

[0027] Figure 3 A schematic diagram showing the cross-sectional outline of a round tube blank and the cross-sectional outline of the tube after processing.

[0028] The components represented by the various reference numerals in the diagram are:

[0029] 1. First roller; 2. Second roller; 3. Drive motor; 4. Shaft seat; 5. Transmission gear set; 6. Displacement control rod; 7. Base; 8. First arc segment; 9. Connecting part; 91. First straight segment; 92. Transition segment; 10. Second arc segment; 11. Second straight segment. Detailed Implementation

[0030] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0031] Example 1

[0032] In a typical embodiment of the present invention, such as Figures 1-3 As shown, a continuously adjustable tube shrinking device is proposed, including: a roller group for continuous roll extrusion tube blank forming, the roller group including a first roller 1 and a second roller 2 arranged opposite to each other, the first roller 1 being located directly above the second roller 2, and cavities being formed on the side walls of the first roller 1 and the second roller 2 along their circumferential direction. Specifically, a first cavity is formed on the side wall of the first roller 1 along its circumferential direction, and a second cavity is formed on the side wall of the second roller 2 along its circumferential direction, the first cavity and the second cavity cooperating with each other.

[0033] The first roller 1 is rotatably mounted on the bearing seat 4 via a rotating shaft, and the second roller 2 is rotatably mounted on the base 7 via a rotating shaft. Both the first roller 1 and the second roller 2 are driven by a drive mechanism and rotate around the shaft. A displacement control rod 6 is fixedly mounted on the bearing seat 4. There is at least one displacement control rod 6, and the displacement control rod 6 is vertically arranged. The bearing seat 4 is connected to the lifting drive mechanism through the displacement control rod 6, which can drive the bearing seat 4 to move vertically, thereby changing the distance between the first roller 1 and the second roller 2, so as to roll extrusion forming different pipe diameters and shapes.

[0034] In this embodiment, the driving mechanism includes a drive machine 3. The output end of the drive machine 3 is connected to the rotating shaft of the second roller 2 so as to drive the second roller 2 to rotate through the drive shaft 3. Transmission gears are fixedly installed on the rotating shafts of the first roller 1 and the second roller 2. The two transmission gears mesh to form a transmission gear set 5, thereby enabling the first roller 1 and the second roller 2 to rotate synchronously through the transmission gear set 5.

[0035] It is understood that in other embodiments, the transmission gear set 5 can also be replaced by a transmission belt pulley assembly, or two drive motors 3 can be set to drive the first roller 1 and the second roller 2 respectively. It is preferable to set two drive motors 3 to avoid restricting the movement of the first roller 1. The specific driving method can be selected according to actual needs, and no further restrictions are imposed here.

[0036] The main body of the drive motor 3 is an electric motor, preferably a servo motor, which can precisely control the amount of rotation and provide a large torque.

[0037] A connecting part 9 is also fixedly provided on the side wall of the first roller 1. The connecting part 9 is located on both sides of the first cavity and is also arranged circumferentially along the side wall of the first roller 1. The connecting part 9 is used to be inserted into the second cavity on the side wall of the second roller 2 to connect the first cavity and the second cavity. When the first roller 1 moves vertically to change its position, it can ensure an effective connection between the first cavity and the second cavity without any gap, and can effectively roll extrude the tube blank to achieve continuous forming of different tube diameters / shapes.

[0038] Specifically, such as Figure 2 As shown, the outline of the first cavity includes a first arc segment 8, and the connecting part 9 includes a first straight segment 91 and a transition segment 92. The first straight segment 91 is located on the outside of the connecting part 9, and the transition segment 92 is located on the inside of the connecting part 9. The transition segment 92 and the first straight segment 91 have an included angle of 4°. The first straight segment 91 is perpendicular to the side wall of the first roller 1, and the transition segment 92 is connected to the first arc segment 8.

[0039] The outline of the second cavity includes a second arc segment 10 and a second straight segment 11. The second straight segment 11 is located at both ends of the second arc segment 10 and is tangent to the second arc segment 10, so as to be used for mating and connecting with the first straight segment 91 (such as clearance fit). The length of the first straight segment 91 is not greater than the length of the second straight segment 11, so as to avoid the connection part 9 from contacting the second arc segment 10 and to ensure the rolling extrusion quality of the tube blank arc surface.

[0040] To ensure the quality of the tube blank during continuous forming and to prevent wrinkling, the dimensions of the first cavity, the second cavity, and the connecting part 9 are limited, as follows:

[0041] 0.4πD≤s1<0.5πD (1);

[0042] 0.4πD≤s2<0.5πD (2);

[0043] s1+s2+2*(a2-a1)<πD (3);

[0044] s1+s2+2*(a2+a1)>πD (4);

[0045] Where D is the diameter of the tube blank, s1 is the length of the first arc segment 8, s2 is the length of the second arc segment 10, a1 is the length of the first straight segment 91, and a2 is the length of the second straight segment 11.

[0046] In addition, it is necessary to ensure that D≤b1≤b2, where b1 is the distance between the two first line segments 91 and b2 is the distance between the two second line segments 11.

[0047] With the design of the above device, the minimum cross-sectional perimeter of the rolled pipe is s1+s2+2*(a2-a1).

[0048] In this embodiment, the first roller 1 and the second roller 2 of the continuously adjustable tube shrinking device both have special surface structures. The first roller 1 can move vertically, and the rotation between the first roller 1 and the second roller 2 can change the perimeter of the tube blank cross section, thereby continuously reducing the perimeter of the tube blank cross section at different axial positions to obtain pre-formed tubes with different diameters at various locations. One set of rollers can produce tube blanks with different perimeter variations, occupying little space and being easy to control. It does not require the pre-layout of several roller sets, which is convenient to use and reduces production costs. Furthermore, the pre-forming process can be combined with various tube forming processes, reducing the difficulty of part forming and broadening the forming capabilities of existing processes.

[0049] Example 2

[0050] In another typical embodiment of this invention, a method for continuous forming of pipe fittings using a continuously adjustable tube shrinking device is proposed, as follows:

[0051] First, adjust the distance between the first roller 1 and the second roller 2, connect the first cavity and the second cavity so that the ends of the first straight segment 91 and the second straight segment 11 are in contact. At this time, the straight segment formed by the first straight segment 91 and the second straight segment 11 is the longest. Then place the tube blank between the first cavity and the second cavity.

[0052] Start the drive mechanism, and the first roller 1 and the second roller 2 rotate to roll the tube blank into shape;

[0053] When tube shrinking is required, the lifting drive mechanism is activated, and the shaft seat 4 is moved downward by a set distance through the displacement control rod 6, reducing the distance between the first roller 1 and the second roller 2, and thus reducing the distance between the first cavity and the second cavity. After tube shrinking is completed, the shaft seat 4 can be raised by the displacement control rod 6, thereby realizing continuously adjustable tube shrinking forming.

[0054] It should be noted that during the upward movement of the bearing 4, the connection between the first straight segment 91 and the second straight segment 11 should be maintained to prevent them from separating.

[0055] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for continuous forming of pipe fittings, employing a continuously adjustable tube shrinking device, characterized in that, The continuously adjustable tube shrinking device includes: a first roller (1) and a second roller (2) connected to a drive motor (3). The first roller (1) is located directly above the second roller (2). A first cavity is provided on the side wall of the first roller (1) along its circumferential direction. A second cavity is provided on the side wall of the second roller (2). The first roller (1) is rotatably mounted on a bearing seat (4). The bearing seat (4) is connected to a lifting drive mechanism through a displacement control rod (6). The second roller (2) is rotatably mounted on a base (7). Connecting parts (9) are fixedly provided on both sides of the first cavity. The connecting parts (9) are arranged along the circumferential direction of the first roller (1). The connecting parts (9) are inserted into the second cavity. The first cavity includes a first arc segment (8), and the connecting part (9) includes a first straight segment (91) and a transition segment (92). The first straight segment (91) is located outside the connecting part (9) and is perpendicular to the side wall of the first roller (1). The transition segment (92) is located inside the connecting part (9) and is connected to the first arc segment (8). The outline of the second cavity includes a second arc segment (10) and a second straight segment (11). The second straight segment (11) is located at both ends of the second arc segment (10) and is tangent to the second arc segment (10). The first straight segment (91) and the second straight segment (11) are in clearance fit. The methods include: Adjust the distance between the first roller (1) and the second roller (2) so that the ends of the first straight segment (91) and the second straight segment (11) are in contact, and place the tube blank between the first cavity and the second cavity; Start the drive machine (3) to roll the tube blank into shape; When tube shrinking is required, the displacement control rod (6) controls the bearing seat (4) to move downward, reducing the distance between the first cavity and the second cavity. After tube shrinking is completed, the displacement control rod (6) controls the bearing seat (4) to rise.

2. The continuous forming method for pipe fittings according to claim 1, characterized in that, The length of the first straight segment (91) is no greater than the length of the second straight segment (11).

3. The continuous forming method for pipe fittings according to claim 1, characterized in that, The transition segment (92) and the first straight segment (91) have an angle between them.

4. The continuous forming method for pipe fittings according to claim 1, characterized in that, The lengths of the first arc segment (8) and the second arc segment (10) are both less than half the circumference of the tube blank, and the lengths of the first arc segment (8) and the second arc segment (10) are both not less than 2 / 5 of the circumference of the tube blank.

5. The continuous forming method for pipe fittings according to claim 1, characterized in that, The maximum perimeter of the space enclosed by the first cavity, the second cavity and the connecting part (9) is greater than the perimeter of the tube blank, and the minimum perimeter is less than the perimeter of the tube blank.

6. The continuous forming method for pipe fittings according to claim 1, characterized in that, The distance between the two first straight segments (91) is not less than the diameter of the tube blank and not greater than the distance between the two second straight segments (11).

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