Method for manufacturing needle-tube double-ballpoint pen tip and needle-tube double-ballpoint pen tip

Abstract

The present application relates to a method for manufacturing a needle-tube double-ballpoint pen tip and a needle-tube double-ballpoint pen tip, wherein the main technical solution is a method for manufacturing a needle-tube double-ballpoint pen tip, which includes the following steps: S1, fixing a pipe fitting; S2, loading a first mold rod and a second mold rod, wherein the outer circumferences of the first mold rod and the second mold rod are both in contact with the inner circumference of the pipe fitting, the hardness of the first mold rod and the second mold rod is greater than the hardness of the pipe fitting, and a cavity groove is provided at the outer edge of the end face of the first mold rod and / or the second mold rod, and the cavity groove is directly opposite the part of the pipe fitting to be dotted; S3, dotting; S4, cutting the installation cavity; S5, installing the first ball and closing the end; S6, installing the second ball; S7, installing the spring. The present application has the advantages of improving the support stability of the first ball and the uniformity of ink output.

Description

Technical Field

[0001] The present application relates to the field of pen tip manufacturing, and in particular to a manufacturing method of a needle-tube double-ballpoint pen tip and a needle-tube double-ballpoint pen tip. Background Art

[0002] The existing needle pen tip is a single ball pen tip, which includes a tube, a ball and a spring. By punching, the tube wall of the tube is stamped with multiple ball seat protrusions, the ball is located in front of the ball seat protrusion, and the spring presses on the ball.

[0003] The multiple ball seat protrusions are mainly used to support and position the ball, and the gaps between the multiple ball seat protrusions form ink outlet channels. The multiple ink outlet channels are evenly distributed to ensure uniform ink outlet.

[0004] Therefore, when the number of ball seat protrusions is greater, the support stability is stronger, and the number of ink outlet channels is greater, which makes the ink outlet more uniform. Existing ball seat protrusions are mostly three or four. The number of ball seat protrusions is limited mainly due to the manufacturing difficulty. Because the ball seat protrusions are stamped, the volume of the ball seat protrusions inside the pipe is large and the molding volume is difficult to control. Therefore, when there are too many ball seat protrusions, the contours of adjacent ball seat protrusions are very likely to interfere with each other, which can cause blockage of the ink outlet channels.

[0005] Therefore, the present application provides a method for manufacturing a needle-tube double-ballpoint pen tip to reduce the difficulty of processing and forming ball seat protrusions greater than four, thereby obtaining a double-ballpoint pen tip with ball seat protrusions greater than four, thereby improving the support stability of the ball and the uniformity of ink output. Summary of the Invention

[0006] In order to improve the support stability of the ball and the uniformity of ink discharge, the present application provides a method for manufacturing a needle tube double-ballpoint pen tip and a needle tube double-ballpoint pen tip.

[0007] The present application provides a method for manufacturing a needle-tube double-ballpoint pen tip, which adopts the following technical solution:

[0008] A method for manufacturing a needle-tube double-ballpoint pen tip comprises the following steps:

[0009] S1. Use fixed tooling to fix the pipe fittings;

[0010] S2. Insert the first mold rod into the pipe from the front end, and insert the second mold rod into the pipe from the rear end. The outer circumferences of the first mold rod and the second mold rod fit the inner circumference of the pipe. The hardness of the first mold rod and the second mold rod is greater than that of the pipe. A mold cavity is formed at the outer edge of the end surface of the first mold rod and / or the second mold rod, and the mold cavity is directly opposite the portion of the pipe to be dotted.

[0011] S3. Dotting the pipe using a dotting mechanism. The inwardly concave portion of the pipe wall is set as a ball seat convex portion. The contour of the ball seat convex portion is adapted to the shape of the cavity groove. There are six ball seat convex portions. Then, the first mold rod and the second mold rod are removed from the pipe.

[0012] S4, turning the front end inner wall of the pipe and the convex portion of the ball seat to form a mounting cavity for mounting the first ball;

[0013] S5. Place the first ball into the installation cavity and squeeze and close the front end of the pipe to confine the first ball in the installation cavity;

[0014] S6. Place the second ball into the pipe from the rear end, and place the spring into the pipe from the rear end, with the front end of the spring abutting against the second ball.

[0015] S7. Mark the pipe wall at the rear end of the pipe fitting. The inwardly concave portion of the pipe wall of the pipe fitting is set as a limiting convex portion, and the rear end of the spring abuts against the limiting convex portion.

[0016] By adopting the above technical solution, by setting the first mold rod and the second mold rod, when making dots, the cavity groove thereon is used to limit the contour shape and protruding volume of the ball seat convex part, thereby reducing the situation where the size of the ball seat convex part is too large due to excessive deviation in the making dots force and accuracy, and then ensuring that a stable size gap is formed between adjacent ball seat convex parts to facilitate the uniformity of ink discharge, and the shape and size of each ball seat convex part are stable and the number is large, and the support stability of the first ball can also be improved.

[0017] Optionally, the outer edges of the opposite end surfaces of the first mold bar and the second mold bar are each provided with six half grooves, and the half grooves are evenly arranged around the circumference of the axis of the first mold bar and the second mold bar, three of the half grooves are set as first half grooves, and the other three half grooves are set as second half grooves, the angle between adjacent first half grooves is 120 degrees, and the angle between two adjacent first half grooves and second half grooves is 60 degrees; in step S2, the end surfaces of the first mold bar and the second mold bar are abutted, and the first half grooves of the first mold bar and the first half grooves of the second mold bar are combined The second half groove of the first mold rod and the second half groove of the second mold rod are combined to form a cavity groove; in step S3, the dotting mechanism includes three dotting needles, and the three dotting needles are evenly arranged around the circumference of the pipe fitting. The dotting process is divided into two times. During the first dotting, the dotting needle is opposite to the position of the cavity groove combined by the first half groove to form three ball seat protrusions, and then the second mold rod drives the pipe fitting to rotate 180 degrees around its own axis, so that the position of the cavity groove combined by the second half groove is opposite to the dotting needle to form another three ball seat protrusions.

[0018] By adopting the above technical solution and using the two-dotting method, the processing of the six ball seat protrusions can be completed successively, thereby reducing the interference of the dotting needles caused by centralized processing and reducing the damage to the pipe wall caused by simultaneous stamping of multiple points on the pipe.

[0019] In addition, the first three ball seat protrusions cooperate with the cavity groove formed by the first half groove, so that the second mold rod and the pipe fitting are relatively fixed, so that the second mold rod can drive the pipe fitting to rotate to adjust the dotting position, which is convenient and quick.

[0020] Optionally, the outer edge of the end face of the first mold bar is provided with three third half grooves evenly arranged around the axis circumference of the first mold bar, and the third half groove is the cavity groove. The outer edge of the end face of the second mold bar is provided with a fourth half groove and a fifth half groove evenly arranged around the axis circumference of the second mold bar, wherein the fifth half groove is the cavity groove; in step S3, the dotting mechanism includes three dotting needles, and the three dotting needles are evenly arranged around the circumference of the tube fitting. The dotting process is divided into two times. During the first dotting, the dotting needle is opposite to the position of the third half groove to form three ball seat protrusions, and then drives the first mold bar and the second mold bar to move relative to the tube fitting toward the front end of the tube fitting, and the three ball seat protrusions are transferred from the third half groove to the fourth half groove of the second mold bar, and then the second mold bar drives the tube fitting to rotate 180 degrees around its own axis so that the position of the fifth half groove is opposite to the dotting needle to form another three ball seat protrusions.

[0021] By adopting the above technical solution, first, during the first dotting, since the angle between adjacent third half grooves on the first mold rod is 120 degrees, that is, the wall thickness of the third half groove is larger, the third half groove with a large wall thickness can more stably constrain the forming contour of the ball seat protrusion, thereby improving the forming stability of the first three ball seat protrusions.

[0022] Secondly, during the second dotting, the three ball seat protrusions are transferred from the third half groove to the fourth half groove of the second mold rod, that is, the first three ball seat protrusions are filled into the fourth half groove, thereby supporting and strengthening the structure between the two adjacent fifth half grooves, thereby reducing the deformation of the groove wall of the fifth half groove during the second dotting process, and then improving the molding stability of the last three ball seat protrusions.

[0023] Optionally, in step S3, after the six ball seat protrusions are punched out, the first mold rod and the second mold rod are taken out of the tube, the first molding rod is inserted into the tube from the front end of the tube, and the second molding rod is inserted into the tube from the rear end of the tube. The relative end faces of the first molding rod and the second molding rod are fixed with three wedge blocks evenly arranged around the circumference, forcing the first molding rod and the second molding rod to approach each other, and the six wedge blocks are respectively inserted into the gaps between the six ball seat protrusions, and the inclined surfaces of the wedge blocks apply extrusion pressure to the surface of the ball seat protrusions to deform the surface of the ball seat protrusions and expand the gaps between the six ball seat protrusions.

[0024] By adopting the above technical solution, the surface of the ball seat convex part is deformed by squeezing the wedge block, and the ball seat convex part becomes slender and conical, and the pit of the ball seat convex part located on the outer peripheral surface of the tube becomes smaller. Therefore, the gap between the six ball seat convex parts is expanded, thereby greatly improving the ink output.

[0025] In addition, the wedge block can shape the contour of the ball seat protrusion through extrusion, so that the gap sizes between the six ball seat protrusions are close to the same, thereby improving the uniformity of ink output.

[0026] Optionally, in step S3, after the first molding rod and the second molding rod approach each other and expand the gap between the six ball seat protrusions, the first molding rod and the second molding rod are moved away from each other, the wedge block is disengaged from the gap between the six ball seat protrusions, and the first molding rod and the second molding rod are rotated 180 degrees respectively. Then, the first molding rod and the second molding rod approach each other, and the propulsion force of the second molding rod is greater than the propulsion force of the first molding rod. The six wedge blocks are respectively stuck in the gaps between the six ball seat protrusions, and the inclined surface of the wedge block applies extrusion pressure to the surface of the ball seat protrusion to deform the surface of the ball seat protrusion.

[0027] By adopting the above technical solution, a second shaping rod is set to drive the pipe to rotate and the work station is switched, so that the six wedge blocks can enter the gaps between the other ball seat protrusions for secondary shaping, making the outer surface of the slender conical ball seat protrusion more uniform, and the supporting effect of the six ball seat protrusions more uniform, thereby improving the positioning and supporting effect of the first ball.

[0028] In addition, by setting the propulsion force, during the secondary molding process when the first molding rod and the second molding rod are close to each other, the propulsion distance of the second molding rod is longer, and the second molding rod squeezes the end of the ball seat protrusion toward the front end of the tube for a short distance, that is, the end of the ball seat protrusion will bend and deform forward, so that the ball seat protrusion has a certain inclination angle. Therefore, the direction in which the force applied by the first ball on the ball seat protrusion will become inclined, thereby increasing the strength of the ball seat protrusion to cope with the force of the first ball, thereby reducing the degree of deformation of the ball seat protrusion, and further improving the support effect on the first ball.

[0029] Optionally, the first mold bar and the second mold bar are both tubular structures, the adjacent ends of the first mold bar and the second mold bar are both closed, and the middle parts of the closed ends of the first mold bar and the second mold bar are both recessed, and the first half groove and the second half groove are both stamped; in step S2, high-pressure gas is injected into the inner cavities of the first mold bar and the second mold bar respectively.

[0030] By adopting the above technical solution, the air pressure of the high-pressure gas is applied to the inner walls of the first mold bar and the second mold bar, thereby greatly improving the rigidity and pressure resistance of the first mold bar and the second mold bar. Therefore, the deformation resistance of the first half groove and the second half groove is greatly improved, thereby reducing the deformation of the groove wall of the first half groove and the second half groove during the dotting process, thereby improving the molding stability of the ball seat convex portion.

[0031] Optionally, the fixed tooling includes a fixed disk, a sleeve and a plurality of jaws, the sleeve is coaxially fixed to the fixed disk, the fixed disk is provided with a through hole corresponding to the barrel mouth of the sleeve, the sleeve is used for the pipe fitting to pass through, the jaws are movably arranged on the fixed disk, the jaws are evenly arranged circumferentially, the sleeve is provided with avoidance holes for avoiding the jaws, the sleeve is connected with a guide tube, the guide tube is arranged radially along the sleeve, and the dotting mechanism includes a plurality of dotting needles; in step S1, the pipe fitting is inserted into the sleeve, the outer circumference of the pipe fitting is fitted with the inner circumference of the sleeve, the clamps are moved, and the clamps are directly clamped on the outer circumference of the pipe fitting through the avoidance holes; in step S3, the dotting needle passes through the guide tube and enters the inner cavity of the sleeve to dot the outer circumference of the pipe fitting.

[0032] By adopting the above technical solution, firstly, by providing the sleeve and the clamping claw, the fixing stability of the pipe is improved, and by providing the guide tube, the straightness of the dotting path of the dotting needle can be improved, thereby improving the dotting accuracy.

[0033] Optionally, in step S2, the positions of the first mold bar and the second mold bar are controlled by a position control mechanism, the position control mechanism includes two linear reciprocating components, a rotation control component and a movable seat, wherein the first mold bar and the second mold bar are respectively installed at the output ends of the two linear reciprocating components, wherein the linear reciprocating component with the second mold bar is installed on the movable seat, and the rotation control component is used to drive the movable seat to rotate around the axis of the second mold bar.

[0034] The present application provides a needle-tube double-ballpoint pen tip, which adopts the following technical solution:

[0035] The invention discloses a needle tube double-ballpoint pen tip, which is manufactured by a needle tube double-ballpoint pen tip manufacturing method.

[0036] In summary, this application includes at least one of the following beneficial technical effects:

[0037] 1. By providing a first mold bar and a second mold bar, the mold grooves thereon define the contour shape and protruding volume of the ball seat protrusions, thereby ensuring a stable gap between adjacent ball seat protrusions. Furthermore, the shape and size of each ball seat protrusion are stable and the number is large, which can also improve the support stability of the first ball.

[0038] 2. By adopting the two-point punching method, the processing of the six ball seat protrusions can be completed successively, thereby reducing the interference of the punching needles caused by centralized processing and reducing the damage to the pipe wall caused by simultaneous punching of multiple points on the pipe fitting;

[0039] 3. The forming stability of the six ball seat protrusions is improved by providing the third, fourth, and fifth half grooves and by changing the positions of the first and second mold bars relative to the tube.

[0040] 4. The wedge-shaped block squeezes the surface of the ball seat protrusion, deforming it into a slender, tapered shape. The recess on the outer circumference of the tube becomes smaller, thereby increasing the gaps between the six ball seat protrusions and making the gaps nearly uniform, greatly improving the ink output and ink uniformity.

[0041] 5. By setting up a tubular first mold bar and a second mold bar, and utilizing the injection of high-pressure gas, the air pressure of the high-pressure gas is applied to the inner walls of the first mold bar and the second mold bar, thereby greatly improving the rigidity and pressure resistance of the first mold bar and the second mold bar, and improving the deformation resistance of the first half groove and the second half groove, thereby reducing the deformation of the groove wall of the first half groove and the second half groove during the dotting process, and thereby improving the molding stability of the ball seat convex portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flowchart of the manufacturing method of Example 1.

[0043] Figure 2 It is a side view of the fixing tool of Example 1.

[0044] Figure 3 It is a front view of the fixing tool of Example 1.

[0045] Figure 4 Schematic diagram of the first mold bar and the second mold bar of Example 1.

[0046] Figure 5 It is a schematic diagram of the position control mechanism of Example 1.

[0047] Figure 6 It is a cross-sectional view of the pipe fitting of Example 1.

[0048] Figure 7 It is a schematic diagram of the processing sequence for embodying the convex portion of the ball seat in Example 1.

[0049] Figure 8 It is a cross-sectional view of the pipe fitting of Example 2.

[0050] Figure 9 Schematic diagram of the transfer air box of Example 2.

[0051] Figure 10 This is a schematic diagram of the processing sequence for embodying the protrusion of the ball seat in Example 3.

[0052] Figure 11 This is a schematic diagram of the first shaping rod and the second shaping rod of Example 4.

[0053] Figure 12 This is a schematic diagram of the molding process sequence for embodying the convex portion of the ball seat in Example 4.

[0054] Explanation of the accompanying symbols: 1. Fixed tooling; 2. Dotting mechanism; 5. First mold rod; 6. Second mold rod; 7. First shaping rod; 8. Second shaping rod; 10. Ball seat protrusion; 11. Fixed plate; 12. Sleeve; 121. Avoidance hole; 13. Clamp; 14. Guide tube; 20. Pipe fitting; 21. Dotting needle; 22. Power assembly; 31. Linear reciprocating assembly; 32. Rotation control assembly; 33. Movable seat; 34. Transfer air box; 35. Air pipe; 51. First half groove; 52. Second half groove; 53. Third half groove; 54. Fourth half groove; 55. Fifth half groove; 71. First wedge block; 81. Second wedge block. DETAILED DESCRIPTION

[0055] The following is combined with Figure 1-12 This application is described in further detail.

[0056] The embodiment of the present application discloses a method for manufacturing a needle-tube double-ballpoint pen tip, which is used to manufacture a needle-tube double-ballpoint pen tip having six ball seat protrusions 10 .

[0057] Reference Figure 1 The manufacturing method of the needle tube double ball pen head comprises the following steps:

[0058] S1, using the fixing tool 1 to fix the pipe fitting 20, the pipe fitting 20 is selected to be a seamless stainless steel pipe that has been cut; Figure 2 、 Figure 3 As shown, the fixed tooling 1 includes a fixed disk 11, a sleeve 12 and a plurality of jaws 13. The fixed disk 11 is fixed externally, and the sleeve 12 is coaxially fixed to the fixed disk 11. The fixed disk 11 is provided with a through hole corresponding to the barrel mouth of the sleeve 12. The sleeve 12 is used for allowing the pipe 20 to pass through. The inner diameter of the sleeve 12 is equal to the outer diameter of the pipe 20. The jaws 13 are movably arranged on the fixed disk 11. The jaws 13 are evenly arranged around the circumference. The movable direction of the jaws 13 is radially of the fixed disk 11. The sleeve 12 is penetrated by an avoidance hole 121 for avoiding the jaws 13. The sleeve 12 is connected with a guide tube 14, and the guide tube 14 is arranged radially along the sleeve 12.

[0059] The specific fixing method is to install the pipe fitting 20 into the sleeve 12, with the outer circumference of the pipe fitting 20 fitting into the inner circumference of the sleeve 12, move the clamp 13, and directly clamp the outer circumference of the pipe fitting 20 through the avoidance hole 121, and then fix the position of the clamp 13 to complete the clamping and fixing of the pipe fitting 20.

[0060] S2, using the position control mechanism to load the first mold bar 5 and the second mold bar 6; Figure 4 As shown, the outer diameter of the first mold bar 5 and the second mold bar 6 is equal to the inner diameter of the tube 20, the hardness of the first mold bar 5 and the second mold bar 6 is greater than the hardness of the tube 20, and the outer edges of the opposite end faces of the first mold bar 5 and the second mold bar 6 are provided with six half grooves, one groove of the half groove passes through the end face of the first mold bar 5, and the other groove of the half groove passes through the outer circumference of the first mold bar 5; each half groove is evenly arranged around the axis of the first mold bar 5 and the second mold bar 6, three of the half grooves are set as first half grooves 51, and the other three half grooves are set as second half grooves 52, the angle between adjacent first half grooves 51 is 120 degrees, and the angle between two adjacent first half grooves 51 and second half grooves 52 is 60 degrees, that is, the first half grooves 51 and the second half grooves 52 are staggered.

[0061] like Figure 5 As shown, the position control mechanism includes two linear reciprocating components 31 and a rotation control component 32 and a movable seat 33, wherein the linear reciprocating component 31 can be a linear drive structure such as a cylinder, an oil cylinder or an electric push rod, and the rotation control component 32 can be a servo motor, etc.; the first mold bar 5 and the second mold bar 6 are respectively installed at the output ends of the two linear reciprocating components 31, wherein the main body of the linear reciprocating component 31 equipped with the first mold bar 5 is externally fixed, and the linear reciprocating component 31 equipped with the second mold bar 6 is installed on the movable seat 33, and the rotation control component 32 is externally fixed, and the rotation control component 32 drives the movable seat 33 to rotate around the axis of the second mold bar 6.

[0062] The two linear reciprocating components 31 control the first mold rod 5 and the second mold rod 6 to slide linearly toward each other, insert the first mold rod 5 into the interior of the pipe fitting 20 from the front end of the pipe fitting 20, and insert the second mold rod 6 into the interior of the pipe fitting 20 from the rear end of the pipe fitting 20. The outer circumferences of the first mold rod 5 and the second mold rod 6 are both in contact with the inner circumference of the pipe fitting 20, and the end faces of the first mold rod 5 and the second mold rod 6 are in contact with each other, so that the first half groove 51 of the first mold rod 5 and the first half groove 51 of the second mold rod 6 are combined to form a cavity groove, and the second half groove 52 of the first mold rod 5 and the second half groove 52 of the second mold rod 6 are combined to form a cavity groove, and the cavity groove is opposite to the part to be punched on the pipe fitting 20.

[0063] S3, using the marking mechanism 2 to mark the pipe 20: Figure 2As shown, the dotting mechanism 2 includes three dotting needles 21 and a power component 22 for driving the dotting needles 21 to move back and forth. The dotting needles 21 are evenly arranged along the circumference of the fixed disk 11, and the dotting needles 21 are radially arranged along the sleeve 12. The dotting needles 21 are slidingly connected to the guide tube 14. The power component 22 can be a cylinder, an oil cylinder or an electric push rod. In this embodiment, the power component 22 adopts a combination of a cam, a return spring and a motor, and utilizes the abutment between the outer peripheral surface of the cam and the end of the dotting needle 21 to drive the dotting needle 21 to move back and forth along its own length direction.

[0064] like Figure 6 、 Figure 7 As shown, the dotting process is divided into two times. During the first dotting, the dotting needle 21 is facing the position of the cavity groove formed by the first half groove 51. The power component 22 drives the dotting needle 21 through the guide tube 14 and enters the inner cavity of the sleeve 12 to punch and dot the outer peripheral surface of the pipe 20 to form three ball seat protrusions 10, and the contour of the ball seat protrusion 10 is adapted to the shape of the cavity groove; during the second dotting, the clamping jaw 13 releases the clamping of the pipe 20, and due to the first three ball seat protrusions 10 and the first half groove 51, the pipe 20 is pressed and dotted. The combined cavity grooves cooperate with each other so that the second mold rod 6 and the tube 20 are relatively fixed, and then the rotation control component 32 is used to drive the movable seat 33 to rotate 180 degrees around the axis of the second mold rod 6, so that the un-marked part of the tube 20 is located on the marking path of the marking needle 21, that is, the position of the cavity groove combined by the second half groove 52 is opposite to the marking needle 21, and then the clamping jaws 13 clamp the tube 20, and the marking needle 21 stamps the outer peripheral surface of the tube 20 to form the other three ball seat protrusions 10.

[0065] The two linear reciprocating assemblies 31 control the first mold bar 5 and the second mold bar 6 to slide linearly apart, that is, to remove the first mold bar 5 and the second mold bar 6 from the tube 20 .

[0066] S4. Turning is performed on the front end inner wall of the pipe 20 and the ball seat protrusion 10 to form a mounting cavity for mounting the first ball.

[0067] S5. Place the first ball into the installation cavity, and squeeze and close the front end of the tube 20 to confine the first ball in the installation cavity.

[0068] S6. Place the second ball into the interior of the tube 20 from the rear end thereof, and place the spring into the interior of the tube 20 from the rear end thereof, with the front end of the spring abutting against the second ball.

[0069] S7. Mark the rear end of the pipe wall of the pipe fitting 20. The inwardly concave portion of the pipe wall of the pipe fitting 20 is set as a limiting convex portion, and the rear end of the spring abuts against the limiting convex portion.

[0070] Example 1 also discloses a needle-tube double-ballpoint pen tip, which is manufactured by the above manufacturing method. The needle-tube double-ballpoint pen tip has six ball seat protrusions 10.

[0071] The implementation principle of Example 1 is: First, when dotting, the cavity grooves of the first mold rod 5 and the second mold rod 6 are used to limit the contour shape and protruding volume of the ball seat protrusion 10 hit by the dotting needle 21, thereby reducing the occurrence of the situation where the size of the ball seat protrusion 10 is too large due to excessive deviation in the dotting force and accuracy, and then ensuring that a stable size gap is formed between the six ball seat protrusions 10 to facilitate uniform ink output.

[0072] Furthermore, six ball seat protrusions 10 are formed, and the ball seat protrusions 10 are large in number and stable in shape, which can significantly improve the support stability of the first ball.

[0073] Secondly, by adopting the two-dotting method, the processing of the six ball seat protrusions 10 can be completed successively, thereby reducing the interference of the dotting needles 21 caused by concentrated processing and reducing the damage to the pipe wall caused by simultaneous punching of multiple points of the pipe 20.

[0074] Example 2

[0075] The difference between Example 2 and Example 1 is that Figure 8 、 Figure 9 As shown, the first mold bar 5 and the second mold bar 6 are both tubular structures, specifically seamless stainless steel tubes, one end of the first mold bar 5 and the second mold bar 6 are both closed, the other end of the first mold bar 5 and the second mold bar 6 has an opening, and the closed ends of the first mold bar 5 and the second mold bar 6 are arranged close to each other.

[0076] The middle part of the closed end of the first mold bar 5 and the second mold bar 6 is stamped with a depression, and the first half groove 51 and the second half groove 52 of the first mold bar 5 and the second mold bar 6 are both stamped. The specific process is to normalize and anneal the first mold bar 5 and the second mold bar 6 in turn to facilitate plastic processing, and then stamp them separately to form the depression at the closed end and the first half groove 51 and the second half groove 52, and then quench the first mold bar 5 and the second mold bar 6 to enhance the hardness and strength of the first mold bar 5 and the second mold bar 6, and finally temper them to eliminate residual stress, stabilize the structure, and reduce cracks and deformation.

[0077] A transfer air box 34 is provided at the connection position between the two linear reciprocating components 31 and the first mold bar 5 and the second mold bar 6. The open ends of the first mold bar 5 and the second mold bar 6 are connected to the transfer air box 34. The transfer air box 34 is also connected to an external air pipe 35, which injects high-pressure gas.

[0078] The specific process is that after loading the first mold rod 5 and the second mold rod 6 into the tube 20, high-pressure gas is injected into the inner cavity of the first mold rod 5 and the second mold rod 6 using the external air pipe 35. The air pressure of the high-pressure gas is applied to the inner wall of the first mold rod 5 and the second mold rod 6, thereby greatly improving the rigidity and pressure resistance of the first mold rod 5 and the second mold rod 6, so that the deformation resistance of the first half groove 51 and the second half groove 52 is greatly improved, thereby reducing the deformation of the groove wall of the first half groove 51 and the second half groove 52 during the dotting process, thereby improving the molding stability of the ball seat protrusion 10.

[0079] Furthermore, the pressure of the high-pressure gas is also applied to the recessed portions of the closed ends of the first mold bar 5 and the second mold bar 6 to enhance the ability of the closed ends of the first mold bar 5 and the second mold bar 6 to resist radial inward contraction.

[0080] Example 3

[0081] The difference between Example 3 and Example 1 is that Figure 10 As shown, the outer edge of the end surface of the first mold bar 5 is provided with three third half grooves 53 evenly arranged around the axis of the first mold bar 5, the angle between adjacent third half grooves 53 is 120 degrees, and the third half grooves 53 are cavity grooves.

[0082] The outer edge of the end face of the second mold bar 6 is provided with a fourth half groove 54 and a fifth half groove 55 evenly arranged around the axis of the second mold bar 6. There are three fourth half grooves 54 and three fifth half grooves 55, and each fourth half groove 54 and each fifth half groove 55 are staggered. The circumferential staggered angle between the fourth half groove 54 and the fifth half groove 55 is 60 degrees, and the fifth half groove 55 is a cavity groove.

[0083] In step S3, during the first dotting, the dotting needle 21 is facing the position of the third half groove 53 to form three ball seat protrusions 10, and then the first mold rod 5 and the second mold rod 6 are moved relative to the tube 20 toward the front end of the tube 20, and the three ball seat protrusions 10 are transferred from the third half groove 53 to the fourth half groove 54 of the second mold rod 6, and then the clamp 13 releases the clamping of the tube 20, and the second mold rod 6 drives the tube 20 to rotate 180 degrees around its own axis, so that the position of the fifth half groove 55 is facing the dotting needle 21, and then the clamp 13 clamps the tube 20, and the dotting needle 21 performs stamping to form another three ball seat protrusions 10.

[0084] First, during the first dotting, since the angle between adjacent third half grooves 53 on the first mold rod 5 is 120 degrees, that is, the wall thickness of the third half groove 53 is relatively large, the third half groove 53 with a large wall thickness can more stably constrain the forming contour of the ball seat protrusion 10, thereby improving the forming stability of the first three ball seat protrusions 10.

[0085] Secondly, during the second dotting, the three ball seat protrusions 10 are transferred from the third half groove 53 to the fourth half groove 54 of the second mold rod 6, that is, the first three ball seat protrusions 10 are filled into the fourth half groove 54, thereby supporting and strengthening the structure between the two adjacent fifth half grooves 55 (including the wall thickness of the fifth half groove 55, the wall thickness of the fourth half groove 54 and the filled ball seat protrusions 10), thereby reducing the deformation of the groove wall of the fifth half groove 55 due to excessive punching pressure, and thereby improving the forming stability of the last three ball seat protrusions 10.

[0086] Example 4

[0087] The difference between Example 4 and Example 1 is that Figure 11 As shown, in step S3, after the six ball seat protrusions 10 are punched out, the first mold rod 5 and the second mold rod 6 are taken out from the tube 20, the first shaping rod 7 is inserted into the tube 20 from the front end thereof, and the second shaping rod 8 is inserted into the tube 20 from the rear end thereof.

[0088] like Figure 11 As shown, three wedge blocks evenly distributed around the circumference are fixed to the opposite end faces of the first shaping rod 7 and the second shaping rod 8. The wedge blocks on the first shaping rod 7 are set as first wedge blocks 71, and the wedge blocks on the second shaping rod 8 are set as second wedge blocks 81. The tips of the wedge blocks are set outward along the axial direction of the pipe 20, and the wedge blocks of the first shaping rod 7 and the second shaping rod 8 are circumferentially staggered, and the staggered angle between adjacent first wedge blocks 71 and second wedge blocks 81 is 60 degrees.

[0089] like Figure 12 As shown, the first shaping rod 7 and the second shaping rod 8 are brought close to each other, and the six wedge blocks are respectively inserted into the gaps between the six ball seat protrusions 10. The inclined surfaces of the wedge blocks apply extrusion force to the surfaces of the ball seat protrusions 10 to deform the surfaces of the ball seat protrusions 10. The ball seat protrusions 10 will become slender and conical, and the recesses of the ball seat protrusions 10 located on the outer peripheral surface of the tube 20 will become smaller, thereby expanding the gaps between the six ball seat protrusions 10 and greatly increasing the ink output.

[0090] Then the first molding rod 7 and the second molding rod 8 are moved away from each other, the wedge blocks are separated from the gaps between the six ball seat protrusions 10, and the first molding rod 7 and the second molding rod 8 are rotated respectively, the rotation angle is 180 degrees, that is, the extrusion station is switched, and then the first molding rod 7 and the second molding rod 8 are moved close to each other, so that the six wedge blocks can enter the gaps between the other ball seat protrusions 10, and the inclined surface of the wedge blocks applies extrusion force to the surface of the ball seat protrusion 10 again, and performs secondary molding, so that the outer surface of the slender conical ball seat protrusion 10 is more uniform, that is, the support effect of the six ball seat protrusions 10 is more uniform, thereby improving the positioning support effect of the first ball and the ink uniformity.

[0091] Moreover, during the secondary molding process, the propulsion force of the second molding rod 8 is made greater than the propulsion force of the first molding rod 7, that is, the propulsion distance of the second molding rod 8 is longer, and the second molding rod 8 squeezes the end of the ball seat protrusion 10 toward the front end of the tube 20 for a short distance, that is, the end of the ball seat protrusion 10 will bend and deform forward, so that the ball seat protrusion 10 has a certain inclination angle. Therefore, the direction in which the force applied by the first ball on the ball seat protrusion 10 will become inclined, and the component of the force is applied to the tube wall of the tube 20, thereby increasing the strength of the ball seat protrusion 10 to cope with the force of the first ball, thereby reducing the degree of deformation of the ball seat protrusion 10, and further improving the support effect on the first ball.

[0092] Furthermore, since the mold can be reshaped later, the cavity grooves of the first mold bar 5 and the second mold bar 6 of Example 4 can be set to be slightly larger than the cavity grooves of Example 1, further reducing the processing difficulty.

[0093] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A method for manufacturing a needle-tube double-ballpoint pen tip, characterized in that: The following steps are involved: S1, using a fixing tool (1) to fix the pipe fitting (20); S2. Insert the first mold rod (5) into the interior of the tube (20) from the front end of the tube (20), and insert the second mold rod (6) into the interior of the tube (20) from the rear end of the tube (20), the outer circumferences of the first mold rod (5) and the second mold rod (6) both fit the inner circumference of the tube (20), the hardness of the first mold rod (5) and the second mold rod (6) is greater than the hardness of the tube (20), and a cavity groove is provided at the outer edge of the end surface of the first mold rod (5) and the second mold rod (6), and the cavity groove is opposite to the part of the tube (20) to be punched; S3, using the dotting mechanism (2) to dot the pipe fitting (20), setting the inwardly concave portion of the pipe wall of the pipe fitting (20) as the ball seat convex portion (10), the contour of the ball seat convex portion (10) being adapted to the shape of the cavity groove, and the number of the ball seat convex portions (10) being six, and then removing the first mold rod (5) and the second mold rod (6) from the pipe fitting (20); S4, turning the front end inner wall of the pipe (20) and the ball seat protrusion (10) to form a mounting cavity for mounting the first ball; S5, placing the first ball into the installation cavity, and squeezing and closing the front end of the pipe (20) to confine the first ball in the installation cavity; S6, placing the second ball into the interior of the tube (20) from the rear end of the tube (20), and placing the spring into the interior of the tube (20) from the rear end of the tube (20), with the front end of the spring abutting against the second ball; S7, dotting the wall of the rear end of the pipe fitting (20), setting the inwardly concave portion of the wall of the pipe fitting (20) as a limiting convex portion, and the rear end of the spring abuts against the limiting convex portion; Six half grooves are provided on the outer edges of the opposite end faces of the first mold bar (5) and the second mold bar (6), and the half grooves are evenly arranged around the axial center circumference of the first mold bar (5) and the second mold bar (6), three of the half grooves are set as first half grooves (51), and the other three half grooves are set as second half grooves (52), the angle between adjacent first half grooves (51) is 120 degrees, and the angle between two adjacent first half grooves (51) and second half grooves (52) is 60 degrees; in step S2, the end faces of the first mold bar (5) and the second mold bar (6) are abutted, the first half groove (51) of the first mold bar (5) and the first half groove (51) of the second mold bar (6) are combined to form a cavity groove, and the first half groove (51) of the first mold bar (5) and the first half groove (51) of the second mold bar (6) are combined to form a cavity groove. The second half groove (52) of the first mold rod (5) and the second half groove (52) of the second mold rod (6) are combined to form a cavity groove; in step S3, the dotting mechanism (2) includes three dotting needles (21), and the three dotting needles (21) are evenly arranged around the circumference of the pipe (20). The dotting process is divided into two times. During the first dotting, the dotting needle (21) is opposite to the position of the cavity groove combined by the first half groove (51) to form three ball seat protrusions (10), and then the second mold rod (6) drives the pipe (20) to rotate 180 degrees around its own axis, so that the position of the cavity groove combined by the second half groove (52) is opposite to the dotting needle (21) to form another three ball seat protrusions (10).

2. A method for manufacturing a needle-tube double-ballpoint pen tip, characterized in that: The following steps are involved: S1, using a fixing tool (1) to fix the pipe fitting (20); S2. Insert the first mold rod (5) into the interior of the tube (20) from the front end of the tube (20), and insert the second mold rod (6) into the interior of the tube (20) from the rear end of the tube (20), the outer circumferences of the first mold rod (5) and the second mold rod (6) both fit the inner circumference of the tube (20), the hardness of the first mold rod (5) and the second mold rod (6) is greater than the hardness of the tube (20), and a cavity groove is provided at the outer edge of the end surface of the first mold rod (5) and the second mold rod (6), and the cavity groove is opposite to the part of the tube (20) to be punched; S3, using the dotting mechanism (2) to dot the pipe fitting (20), setting the inwardly concave portion of the pipe wall of the pipe fitting (20) as the ball seat convex portion (10), the contour of the ball seat convex portion (10) being adapted to the shape of the cavity groove, and the number of the ball seat convex portions (10) being six, and then removing the first mold rod (5) and the second mold rod (6) from the pipe fitting (20); S4, turning the front end inner wall of the pipe (20) and the ball seat protrusion (10) to form a mounting cavity for mounting the first ball; S5, placing the first ball into the installation cavity, and squeezing and closing the front end of the pipe (20) to confine the first ball in the installation cavity; S6, placing the second ball into the interior of the tube (20) from the rear end of the tube (20), and placing the spring into the interior of the tube (20) from the rear end of the tube (20), with the front end of the spring abutting against the second ball; S7, dotting the wall of the rear end of the pipe fitting (20), setting the inwardly concave portion of the wall of the pipe fitting (20) as a limiting convex portion, and the rear end of the spring abuts against the limiting convex portion; The outer edge of the end surface of the first mold bar (5) is provided with three third half grooves (53) evenly arranged around the axis circumference of the first mold bar (5), and the third half grooves (53) are the cavity grooves. The outer edge of the end surface of the second mold bar (6) is provided with a fourth half groove (54) and a fifth half groove (55) evenly arranged around the axis circumference of the second mold bar (6), wherein the fifth half groove (55) is the cavity groove. In step S3, the dotting mechanism (2) includes three dotting needles (21), and the three dotting needles (21) are evenly arranged around the circumference of the pipe (20). The dotting process is divided into two times, the first During one dotting operation, the dotting needle (21) is aligned with the position of the third half groove (53) to form three ball seat protrusions (10), and then the first mold rod (5) and the second mold rod (6) are driven to move relative to the pipe (20) toward the front end of the pipe (20), and the three ball seat protrusions (10) are transferred from the third half groove (53) to the fourth half groove (54) of the second mold rod (6), and then the second mold rod (6) drives the pipe (20) to rotate 180 degrees around its own axis, so that the position of the fifth half groove (55) is aligned with the dotting needle (21), so as to form another three ball seat protrusions (10).

3. The method for manufacturing a needle-tube double-ballpoint pen tip according to claim 1 or 2, characterized in that: In step S3, after the six ball seat protrusions (10) are punched out, the first mold rod (5) and the second mold rod (6) are taken out from the pipe fitting (20), the first shaping rod (7) is inserted into the pipe fitting (20) from the front end thereof, and the second shaping rod (8) is inserted into the pipe fitting (20) from the rear end thereof. The opposite end faces of the first shaping rod (7) and the second shaping rod (8) are fixed with three wedge blocks evenly arranged around the circumference, forcing the first shaping rod (7) and the second shaping rod (8) to approach each other. The six wedge blocks are respectively inserted into the gaps between the six ball seat protrusions (10), and the inclined surfaces of the wedge blocks apply a squeezing force to the surface of the ball seat protrusion (10) to deform the surface of the ball seat protrusion (10) and expand the gaps between the six ball seat protrusions (10).

4. The method for manufacturing a double-ballpoint pen tip according to claim 3, wherein: In step S3, after the first shaping rod (7) and the second shaping rod (8) are brought closer to each other and the gaps between the six ball seat protrusions (10) are enlarged, the first shaping rod (7) and the second shaping rod (8) are moved away from each other, the wedge blocks are separated from the gaps between the six ball seat protrusions (10), and the first shaping rod (7) and the second shaping rod (8) are rotated 180 degrees respectively. Then, the first shaping rod (7) and the second shaping rod (8) are brought closer to each other, and the propulsion force of the second shaping rod (8) is greater than the propulsion force of the first shaping rod (7). The six wedge blocks are respectively inserted into the gaps between the six ball seat protrusions (10), and the inclined surfaces of the wedge blocks apply extrusion force to the surfaces of the ball seat protrusions (10) to deform the surfaces of the ball seat protrusions (10).

5. The method for manufacturing a double-ballpoint pen tip according to claim 1, characterized in that: The first mold bar (5) and the second mold bar (6) are both tubular structures, the adjacent ends of the first mold bar (5) and the second mold bar (6) are both closed, and the middle parts of the closed ends of the first mold bar (5) and the second mold bar (6) are both recessed, and the first half groove (51) and the second half groove (52) are both stamped; in step S2, high-pressure gas is injected into the inner cavities of the first mold bar (5) and the second mold bar (6), respectively.

6. The method for manufacturing a needle-tube double-ballpoint pen tip according to claim 1 or 2, characterized in that: The fixing tool (1) comprises a fixing plate (11), a sleeve (12) and a plurality of clamping claws (13), the sleeve (12) is fixed coaxially with the fixing plate (11), the fixing plate (11) is provided with a through hole corresponding to the barrel mouth of the sleeve (12), the sleeve (12) is used for allowing the pipe (20) to pass through, the clamping claws (13) are movably arranged on the fixing plate (11), the clamping claws (13) are evenly arranged around the circumference, the sleeve (12) is penetrated by a avoidance hole (121) for avoiding the clamping claws (13), the sleeve (12) is connected to a guide pipe (1 4), the guide tube (14) is arranged radially along the sleeve (12), and the dotting mechanism (2) includes a plurality of dotting needles (21); in step S1, the pipe (20) is inserted into the sleeve (12), the outer peripheral surface of the pipe (20) is in contact with the inner peripheral surface of the sleeve (12), and the clamping jaws (13) are moved, and the clamping jaws (13) are directly clamped on the outer peripheral surface of the pipe (20) through the avoidance hole (121); in step S3, the dotting needles (21) pass through the guide tube (14) and enter the inner cavity of the sleeve (12) to dot the outer peripheral surface of the pipe (20).

7. The method for manufacturing a needle-tube double-ballpoint pen tip according to claim 1 or 2, characterized in that: In step S2, the positions of the first mold bar (5) and the second mold bar (6) are controlled by a position control mechanism, the position control mechanism comprising two linear reciprocating components (31), a rotation control component (32) and a movable seat (33), wherein the first mold bar (5) and the second mold bar (6) are respectively mounted on the output ends of the two linear reciprocating components (31), wherein the linear reciprocating component (31) equipped with the second mold bar (6) is mounted on the movable seat (33), and the rotation control component (32) is used to drive the movable seat (33) to rotate around the axis of the second mold bar (6).

8. A needle-tube double-ballpoint pen tip, characterized by: The invention is manufactured by the manufacturing method of the needle tube double ballpoint pen tip according to claim 1 or 2.

Images