Special-shaped thin-wall short pipe bending forming tool and forming machining method

Abstract

The invention belongs to the technical field of precise short pipe bending forming machining, and discloses a special-shaped thin-wall short pipe bending forming tool and a forming machining method.The special-shaped thin-wall short pipe bending forming tool comprises a clamping component, a bending component and a base flat plate; the clamping part comprises an arc-shaped seat and a clamping plate; the bending component comprises an L-shaped pressing rod guide plate, a hand-pulling pressing rod, an elbow pressing rod and a rotating elbow. The special-shaped thin-wall short pipe bending forming machining method is achieved by adopting the special-shaped thin-wall short pipe bending forming tool in the first scheme and comprises the following steps that firstly, the tool is fixed, secondly, the short pipe is positioned, thirdly, the short pipe is clamped, fourthly, the short pipe is bent, and fifthly, the tool is reset. The problem that due to the fact that the thin-wall short pipe is not long enough, bending clamping is not facilitated is solved. Limiting, clamping and fixing are reliable, and adjustment and operation are convenient.

Description

Technical Field

[0001] The invention relates to a special-shaped thin-wall short tube bending forming tool and a forming processing method, belonging to the technical field of precision short tube bending forming processing. Background Art

[0002] At present, the bending of slender straight tubes adopts the forming method of tube bender, which is suitable for the tubes with long enough ends of the bending radius, and the length is greater than the minimum length of the clamping end and the bending end required by the tube bender, so that it can be bent and formed in one time. If the axial expansion length of the tube is short, and the two ends of the bending radius are less than the minimum length of the clamping end and the bending end, the material can generally be lengthened according to the sum of the sizes of the clamping end and the bending end of the tube bender to ensure sufficient length of the clamping end and the bending end, first bend and form, and then shorten the two ends according to the part size requirements. This method is suitable for straight tube production.

[0003] The hydraulic bending conduit used in a certain equipment has a drum-shaped curved surface structure on both ends. The tube is short and thin-walled. A side wall hole is opened on the straight section. The side wall hole has an angular requirement with the bending angle. The side wall hole is on the neutral surface of the pipe after bending. Before the bending process of the special-shaped thin-walled short tube, a thick-walled tube with the same inner diameter as the finished tube is first used to turn the drum-shaped curved surface on both ends and the thin-walled section in the middle to form a semi-finished product. Since the semi-finished tube is short in length and has drum-shaped curved surfaces on both ends, it cannot be bent by a tube bender.

[0004] Therefore, it is necessary to make a special-purpose bending tool for special-shaped thin-walled short tubes. The tool needs to be fixed and clamped reliably, ensure accurate limit, and meet technical requirements such as simple and convenient bending and forming operations and high efficiency. In addition, in order to simplify the forming process of the part as much as possible, the side wall holes opened on the straight section can be drilled with a drill jig before bending and forming. This process does not need to limit its angular direction, avoiding the problem of drilling holes after bending and forming that is not conducive to ensuring the angular requirements of the center of the side wall holes. The angular position of the side wall holes is guaranteed by the angular limit pin in the bending tool. Summary of the invention

[0005] The purpose of the present invention is to provide a tooling and forming method for bending and forming a special-shaped thin-walled short tube. The technical solution adopted by the present invention is as follows:

[0006] Solution 1: A tool for bending and forming a special-shaped thin-walled short tube includes a clamping component, a bending component, and a base plate;

[0007] The clamping component comprises an arc seat and a clamping plate; an arc groove and a drum-shaped upper limit groove equal to the outer diameter of the thin-walled short tube are provided on one longitudinal side of the arc seat; a drum-shaped lower limit groove is provided on the clamping plate; the arc seat and the clamping plate are installed on the base plate, and the drum-shaped upper limit groove and the drum-shaped lower limit groove are correspondingly provided to form a limit groove, and the drum-shaped convex arc surface of the thin-walled short tube is placed in the limit groove;

[0008] The bending components include an L-shaped pressure rod guide plate, a hand pressure rod, an elbow pressure rod, and a rotating elbow;

[0009] The horizontal part of the L-shaped pressure rod guide plate is installed on the base plate, and the upper end of the vertical part of the L-shaped pressure rod guide plate is hinged to the left end of the hand pressure rod; the horizontal part of the L-shaped pressure rod guide plate is provided with a longitudinal hole; the upper end of the elbow pressure rod is in contact with the hand pressure rod, and the lower end of the elbow pressure rod is hinged to the rotating elbow through the longitudinal hole, and the arc groove of the rotating elbow is fitted on the thin-walled short tube.

[0010] Furthermore, a screw hole is provided in the middle of the horizontal portion of the L-shaped pressure rod guide plate, an adjustable limit screw is installed in the screw hole, and a nut is threadedly connected to the adjustable limit screw to limit the downward stroke of the hand pressure rod.

[0011] Furthermore, a return spring is mounted on the elbow pressure rod, and the return spring is arranged between the horizontal part of the L-shaped pressure rod guide plate and the hand-operated pressure rod.

[0012] Furthermore, an arc-shaped groove is provided on the bottom surface of the rotating elbow, the curvature of the arc-shaped groove is equal to the curvature of the outer diameter of the thin-walled short tube, and the arc-shaped groove matches the wall surface of the thin-walled short tube.

[0013] Furthermore, a limiting guide groove is opened on the arc-shaped groove, a side wall hole is processed on the side wall of the thin-walled short tube, an angular limiting pin is installed in the side wall hole, and the extended end of the angular limiting pin is clearance-matched with the limiting guide groove.

[0014] Option 2:

[0015] A method for bending and forming a special-shaped thin-walled short tube is implemented by using the special-shaped thin-walled short tube bending and forming tooling described in Scheme 1, and comprises the following steps:

[0016] Step 1: Fix the tooling and clamp the base plate on the flat-nose pliers;

[0017] Step 2: Position the short tube, insert the glue stick into the thin-walled short tube, and extend both ends of the glue stick out of the thin-walled short tube. A limit retaining ring groove is provided at the left end of the glue stick, and an open retaining ring is inserted into the limit retaining ring groove. The inner end face of the retaining ring is in contact and aligned with the left end face of the thin-walled short tube; align the side wall hole limit pin guide groove on the glue stick with the side wall hole on the thin-walled short tube, insert the angular limit pin into the side wall hole, and then place the drum-shaped convex arc surface of the thin-walled short tube in the limit groove, and use the drum-shaped convex arc surface for axial positioning;

[0018] Step 3: Clamp the short tube, manually apply force to the hand lever, drive the rotating elbow to approach the thin-walled short tube through the elbow lever, and clamp the rotating elbow and the thin-walled short tube;

[0019] Step 4: Bend the short tube. Operate the handle of the hand-operated pressure rod to push the elbow pressure rod to drive the rotating elbow to move downward. The reset spring is compressed and stored. Continue to apply force to the hand-operated pressure rod. The elbow continues to move downward. Since the thin-walled short tube is cantilevered and clamped, the reverse force on the arc surface of the elbow and the tube wall is asymmetric. The elbow moves downward with the elbow pressure rod until the hand-operated pressure rod touches the end of the limit screw. The hand-operated pressure rod stops applying force, and the thin-walled short tube is bent to the required angle.

[0020] Step 5. Reset the tooling, loosen or operate the handle of the hand-operated pressure rod in the opposite direction. The elbow pressure rod moves in the opposite direction under the action of the rebound force of the reset spring. The elbow pressure rod and the elbow move in the opposite direction to the initial position. Loosen the fixing screws of the splint, withdraw the splint backward, take out the bent thin-walled short tube, remove the angular limit pin and the open retaining ring on the glue stick, pull out the glue stick, and complete the bending of the special-shaped thin-walled short tube.

[0021] Beneficial effects of the present invention

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The clamping plate structure uses the drum-shaped surface at the end of the thin-walled short tube as the clamping surface. The limit clamping and fixing are reliable, and the adjustment and operation are convenient. It solves the problem of the thin-walled short tube being not long enough and not conducive to bending and clamping.

[0024] 2. The downward pressure rotating elbow structure is adopted. When the short tube is bent downward, the outer wall of the short tube slides in the arc groove of the elbow. As the downward pressure stroke increases, the elbow rotates with the shape. The size of the elbow can be set according to the length of the bending end;

[0025] 3. Use internal support rubber rods to effectively prevent defects such as local depression and deformation when thin-walled short tubes are bent;

[0026] 4. Use the elbow limit guide groove to guide the limit pin of the side wall hole, so that the angular direction of the side wall hole of the short tube can be guaranteed. The limit method is reliable and convenient. There is no need to re-align the angular direction of the side wall hole after bending, which reduces the process;

[0027] 5. Use the adjustable limit screw to fine-tune the downward stroke of the hand plate pressure rod and the elbow pressure rod, which can easily adjust the bending angle of the thin-walled short tube. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 Three-dimensional bending tooling for special-shaped thin-walled short tubes Figure 1 ;

[0029] Figure 2 Three-dimensional bending tooling for special-shaped thin-walled short tubes Figure 2 ;

[0030] Figure 3It is a schematic diagram of the assembly structure of the thin-walled short tube, the glue stick, the side wall hole, and the angular limit pin before bending;

[0031] Figure 4 It is a schematic diagram of the rotating elbow structure;

[0032] Figure 5 It is a schematic diagram of the arc seat structure;

[0033] Figure 6 is a schematic diagram of the splint structure;

[0034] Figure 7 This is a schematic diagram of the structure of a special-shaped thin-walled short tube before bending;

[0035] Figure 8 This is a schematic diagram of the structure of a special-shaped thin-walled short tube after bending.

[0036] In the figure: 1. thin-walled short tube, 1-1. drum-shaped convex arc surface, 1-2. side wall hole, 2. angular limit pin, 3. glue stick, 3-1. limit pin guide groove, 4. open retaining ring, 5. arc seat, 5-1. arc groove, 5-2. drum-shaped upper limit groove, 6. clamping plate, 6-1. drum-shaped lower limit groove, 7. screw washer combination, 8. pressure rod guide plate, 8-1. vertical part, 9. first pin shaft, 10. hand plate pressure rod, 11. limit screw, 12. locking nut, 13. reset spring, 14. elbow pressure rod, 15. rotating elbow, 15-1. arc groove, 15-2. limit guide groove, 16. second pin shaft, 17. base plate. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is described below by the specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0038] The present invention will be further described in detail below in conjunction with the accompanying drawings. The following embodiments are provided to explain the present invention, but the present invention is not limited to the following embodiments.

[0039] Embodiment 1:

[0040] A tool for bending and forming a special-shaped thin-walled short tube includes a clamping component, a bending component, and a base plate 17;

[0041] The clamping component includes an arc seat 5 and a clamping plate 6; an arc groove 5-1 and a drum-shaped upper limit groove 5-2 having the same outer diameter as the thin-walled short tube 1 are provided on one longitudinal side of the arc seat 5; a drum-shaped lower limit groove 6-1 is provided on the clamping plate 6; the arc seat 5 and the clamping plate 6 are installed on the base plate 17, and the drum-shaped upper limit groove 5-2 and the drum-shaped lower limit groove 6-1 are correspondingly provided to form a limit groove, and the drum-shaped convex arc surface 1-1 of the thin-walled short tube 1 is placed in the limit groove;

[0042] The bending component includes an L-shaped pressure rod guide plate 8, a hand pressure rod 10, an elbow pressure rod 14, and a rotating elbow 15;

[0043] The horizontal part of the L-shaped pressure rod guide plate 8 is installed on the base plate 17, and the upper end of the vertical part 8-1 of the L-shaped pressure rod guide plate 8 is hinged to the left end of the hand pressure rod 10 through the first pin shaft 9; the horizontal part of the L-shaped pressure rod guide plate 8 is provided with a longitudinal hole; the upper end of the elbow pressure rod 14 is in contact with the hand pressure rod 10, and the lower end of the elbow pressure rod 14 passes through the longitudinal hole and is hinged to the rotating elbow 15 through the second pin shaft 16, and the arc groove 15-1 of the rotating elbow 15 is fitted on the thin-walled short tube 1.

[0044] Furthermore, a screw hole is provided in the middle of the horizontal portion of the L-shaped pressure rod guide plate 8, an adjustable limit screw 11 is installed in the screw hole, and a nut 12 is threadedly connected to the adjustable limit screw (11) to limit the downward stroke of the hand pressure rod 10.

[0045] Furthermore, a return spring 13 is sleeved on the elbow pressure rod 14 , and the return spring 13 is arranged between the horizontal portion of the L-shaped pressure rod guide plate 8 and the hand pressure rod 10 .

[0046] Furthermore, an arc-shaped groove 15 - 1 is provided on the bottom surface of the rotating elbow 15 , the curvature of the arc-shaped groove 15 - 1 is equal to the curvature of the outer diameter of the thin-walled short tube 1 , and the arc-shaped groove 15 - 1 matches the wall surface of the thin-walled short tube 1 .

[0047] Furthermore, a limiting guide groove 15-2 is opened on the arc groove 15-1, a side wall hole 1-2 is processed on the side wall of the thin-walled short tube 1, an angular limiting pin 2 is installed in the side wall hole 1-2, and the extended end of the angular limiting pin 2 is gap-matched with the limiting guide groove 15-2.

[0048] Embodiment 2:

[0049] A method for bending and forming a special-shaped thin-walled short tube is implemented by using the special-shaped thin-walled short tube bending and forming tooling described in Example 1, comprising the following steps:

[0050] Step 1: Fix the tooling and clamp the base plate 17 on the flat-nose pliers;

[0051] Step 2, positioning the short tube, insert the glue stick 3 into the thin-walled short tube 1, and the two ends of the glue stick 3 extend out of the thin-walled short tube 1. The left end of the glue stick 3 is provided with a limit retaining ring groove, and the open retaining ring 4 is inserted into the limit retaining ring groove. The inner end face of the retaining ring 4 is in contact and aligned with the left end face of the thin-walled short tube 1; align the side wall hole limit pin guide groove 3-1 on the glue stick 3 with the side wall hole 1-2 on the thin-walled short tube 1, insert the angular limit pin 2 into the side wall hole 1-2, and then place the drum-shaped convex arc surface 1-1 of the thin-walled short tube 1 in the limit groove, and use the drum-shaped convex arc surface 1-1 for axial positioning;

[0052] Step 3: Clamp the short tube. Apply force manually to the hand pressure rod 10, drive the rotating elbow 15 to approach the thin-walled short tube 1 through the elbow pressure rod 14, align the limiting guide groove 15-2 on the elbow with the extended end of the limiting pin 2 on the thin-walled short tube 1, and use the drum-shaped concave arc surface 6-1 of the clamping plate 6 to close the drum-shaped convex arc surface 1-1 of the thin-walled short tube 1, and tighten the clamping plate 6 with the screw washer combination 7 to complete the positioning and clamping of the thin-walled short tube 1 on the tooling;

[0053] Step 4: bend the short tube. Operate the handle of the hand-pull pressure rod 10 to push the elbow pressure rod 14 to drive the rotating elbow 15 to move downward. The reset spring 13 is compressed and stores energy. Continue to apply force to the hand-pull pressure rod 10, and the elbow 15 continues to move downward. Since the thin-walled short tube 1 is a cantilever positioning clamp, the reverse force on the arc surface of the elbow 15 that fits the tube wall is asymmetric. The elbow 15 moves downward with the elbow pressure rod 14 until the hand-pull pressure rod 10 touches the end of the limit screw 11. The hand-pull pressure rod 10 stops applying force, and the thin-walled short tube 1 is bent to the required angle.

[0054] Step 5, reset the tooling, loosen or operate the handle of the hand-pull pressure rod 10 in the opposite direction, the elbow pressure rod 14 moves in the opposite direction under the action of the rebound force of the reset spring 13, the elbow pressure rod 14 and the elbow 15 move in the opposite direction to the initial position, loosen the fixing screw 7 of the splint 6, withdraw the splint 6 backward, take out the bent thin-walled short tube 1, remove the angular limit pin 2 and the opening retaining ring 4 on the glue stick 3, pull out the glue stick 3, and complete the bending of the special-shaped thin-walled short tube.

[0055] The above embodiments are merely illustrative of the present invention and do not limit its protection scope. Those skilled in the art may also make partial changes thereto, and as long as they do not exceed the spirit of the present invention, they are all within the protection scope of the present invention.

Claims

1. A tool for bending and forming a special-shaped thin-walled short tube, characterized in that: It comprises a clamping component, a bending component and a base plate (17); The clamping component comprises an arc seat (5) and a clamping plate (6); an arc groove (5-1) having an outer diameter equal to that of the thin-walled short tube (1) and a drum-shaped upper limit groove (5-2) are provided on one longitudinal side of the arc seat (5); a drum-shaped lower limit groove (6-1) is provided on the clamping plate (6); the arc seat (5) and the clamping plate (6) are mounted on a base plate (17), and the drum-shaped upper limit groove (5-2) and the drum-shaped lower limit groove (6-1) are correspondingly provided to form a limit groove, and the drum-shaped convex arc surface (1-1) of the thin-walled short tube (1) is placed in the limit groove; The bending component comprises an L-shaped pressure rod guide plate (8), a hand-operated pressure rod (10), an elbow pressure rod (14), and a rotating elbow (15); The horizontal portion of the L-shaped pressure rod guide plate (8) is mounted on a base plate (17), and the upper end of the vertical portion (8-1) of the L-shaped pressure rod guide plate (8) is hinged to the left end of the hand-operated pressure rod (10); the horizontal portion of the L-shaped pressure rod guide plate (8) is provided with a longitudinal hole; the upper end of the elbow pressure rod (14) is in contact with the hand-operated pressure rod (10), and the lower end of the elbow pressure rod (14) passes through the longitudinal hole and is hinged to the rotating elbow (15), and the arc groove (15-1) of the rotating elbow (15) is fitted on the thin-walled short tube (1).

2. The tooling for bending and forming a special-shaped thin-walled short tube according to claim 1 is characterized in that: A screw hole is provided in the middle of the horizontal part of the L-shaped pressure rod guide plate (8), and an adjustable limit screw (11) is installed in the screw hole. A nut (12) is threadedly connected to the adjustable limit screw (11) to limit the downward stroke of the hand pressure rod (10).

3. The tooling for bending and forming a special-shaped thin-walled short tube according to claim 2 is characterized in that: The elbow pressure rod (14) is sleeved with a return spring (13), and the return spring (13) is arranged between the horizontal part of the L-shaped pressure rod guide plate (8) and the hand pressure rod (10).

4. The tooling for bending and forming a special-shaped thin-walled short tube according to claim 3 is characterized in that: An arc-shaped groove (15-1) is provided on the bottom surface of the rotating elbow (15); the curvature of the arc-shaped groove (15-1) is equal to the curvature of the outer diameter of the thin-walled short tube 1; and the arc-shaped groove (15-1) matches the wall surface of the thin-walled short tube (1).

5. The tooling for bending and forming a special-shaped thin-walled short tube according to claim 4 is characterized in that: The arc-shaped groove (15-1) is provided with a limit guide groove (15-2), the side wall of the thin-walled short tube (1) is processed with a side wall hole (1-2), the angular limit pin (2) is installed in the side wall hole (1-2), and the extended end of the angular limit pin (2) is clearance-matched with the limit guide groove (15-2).

6. A method for bending and forming a special-shaped thin-walled short tube, characterized in that: The process of bending and forming the special-shaped thin-walled short tube according to claim 5 is implemented by using the bending and forming tooling according to claim 5, comprising the following steps: Step 1: Fix the tooling and clamp the base plate (17) on a flat-nose pliers; Step 2, positioning the short tube, inserting the glue stick (3) into the thin-walled short tube (1), with both ends of the glue stick (3) extending out of the thin-walled short tube (1), a limit retaining ring groove is provided at the left end of the glue stick (3), an open retaining ring (4) is inserted into the limit retaining ring groove, and the inner end surface of the retaining ring (4) is in contact with and aligned with the left end surface of the thin-walled short tube (1); aligning the side wall hole limit pin guide groove (3-1) on the glue stick (3) with the side wall hole (1-2) on the thin-walled short tube (1), inserting the angular limit pin (2) into the side wall hole (1-2), and then placing the drum-shaped convex arc surface (1-1) of the thin-walled short tube (1) in the limit groove, and using the drum-shaped convex arc surface (1-1) for axial positioning; Step 3: Clamp the short tube, manually apply force to the hand pressure rod (10), drive the rotating elbow (15) to approach the thin-walled short tube (1) through the elbow pressure rod (14), and clamp the rotating elbow (15) and the thin-walled short tube (1); Step 4: bend the short tube. Operate the handle of the hand-operated pressure rod (10) to push the elbow pressure rod (14) to drive the rotating elbow (15) to move downward. The return spring (13) is compressed and stores energy. Continue to apply force to the hand-operated pressure rod (10). The elbow (15) continues to move downward. Since the thin-walled short tube (1) is a cantilever positioning clamp, the reverse force on the curved surface of the elbow (15) that fits the tube wall is asymmetrical. The elbow (15) moves downward with the elbow pressure rod (14) until the hand-operated pressure rod (10) touches the end of the limit screw (11). The hand-operated pressure rod (10) stops applying force, and the thin-walled short tube (1) is bent to the required angle. Step 5, reset the tooling, loosen or operate the handle of the hand-operated pressure rod (10) in the opposite direction, the elbow pressure rod (14) moves in the opposite direction under the action of the rebound force of the reset spring (13), the elbow pressure rod (14) and the elbow (15) move in the opposite direction to the initial position, loosen the fixing screw (7) of the clamp (6), withdraw the clamp (6) backward, take out the bent thin-walled short tube (1), remove the angular limit pin (2) and the opening retaining ring (4) on the glue stick (3), pull out the glue stick (3), and complete the bending of the special-shaped thin-walled short tube.

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