An injection mold for manufacturing an automotive piston tube with a metal insert and an injection method thereof

Abstract

The present invention provides an injection mold for manufacturing an automotive piston tube with a metal insert, which includes a rear mold base, a rear mold core, a front mold core, a positioning mechanism and an auxiliary fixing system. A concave fixing groove is provided on the rear mold base, and the rear mold core is fixed in the fixing groove. The front mold core is arranged above the rear mold core, and the space enclosed between the front mold core and the rear mold core forms an injection runner. A gate is provided on the front mold core. The positioning mechanism for limiting and fixing the metal insert is embedded in the rear mold core, and one end of the positioning mechanism extends into the rear mold cavity of the rear mold core. The auxiliary fixing system is arranged on the side of the rear mold base and is used for fixing the metal insert. The present invention also provides an injection molding method, in which the metal insert is limited and fixed by the positioning mechanism fixed on the rear mold core, then fixed by the auxiliary fixing system, and finally the rear mold core and the front mold core are clamped for injection molding. The present invention has the characteristics of simple structure, reliable positioning and convenient operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of injection molds, and particularly relates to an injection mold for manufacturing an automotive piston tube with a metal insert and an injection method thereof. Background Art

[0002] Molds are known as the "mother of industry". They mainly endow or manufacture components with corresponding appearances and structures by changing the shapes of molten or liquid materials. Compared with other types of molds, injection molds are the most widely used in manufacturing and are suitable for the production of precision and complex products. In mold manufacturing, some special injection molded parts are inlaid with metal inserts inside. The method of using plastic materials to wrap metal materials can improve the strength and durability of the injection molded parts, etc., and has a wide range of applications.

[0003] For the preparation of such injection molded parts with metal inserts, the current injection mold structures are complex, the positioning operations are troublesome, and the reliability is not high. There is an urgent need for an injection mold for manufacturing injection molded parts with metal inserts and an injection method thereof that can overcome the above problems. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the above-mentioned existing technologies, and provide an injection mold for manufacturing an automotive piston tube with a metal insert and an injection method thereof. The metal insert is limited and fixed by a positioning mechanism fixed on the rear mold core, and then fixed by an auxiliary fixing system. Finally, the rear mold core and the front mold core are clamped for injection molding, which has the characteristics of simple structure, reliable positioning, and convenient operation.

[0005] The present invention provides an injection mold for manufacturing an automotive piston tube with a metal insert, including a rear mold base, a rear mold core, a front mold core, a positioning mechanism, and an auxiliary fixing system. An inwardly concave fixing groove is provided on the rear mold base, and the rear mold core is fixed in the fixing groove. The front mold core is arranged above the rear mold core, and the space enclosed between the front mold core and the rear mold core forms an injection runner. A gate is provided on the front mold core. The positioning mechanism for limiting and fixing the metal insert is embedded in the rear mold core. One end of the positioning mechanism extends into the rear mold cavity of the rear mold core. The auxiliary fixing system is arranged on the side of the rear mold base and is used to fix the metal insert positioned at one end of the positioning mechanism.

[0006] Furthermore, the positioning mechanism includes a positioning insert block, at least one positioning magnetic column for magnetically fixing the metal insert, and at least one positioning insert pin for cooperating with the limiting hole of the metal insert for fixing. The first end face of the positioning insert block embedded in the rear mold core is flush with the lower bottom face of the rear mold core. The positioning magnetic column is arranged on the second end face of the positioning insert block. The positioning insert pin extends from the first end face of the positioning insert block, and one end of the positioning insert pin protrudes from the second end face of the positioning insert block.

[0007] Further, the front mold core includes a first front mold core, a second front mold core, a first slider system and a second slider system. The second front mold core is fixed to the front mold base. The first front mold core is fixed by an auxiliary fixing system. The first slider system includes a first slider and a first sliding device. The second slider system includes a second slider and a second sliding device. Both the first slider system and the second slider system are fixed to the rear mold base. The rear mold base is provided with a first chute and a second chute for the first slider and the second slider to slide respectively. The first slider and the second slider slide along the first chute and the second chute respectively driven by the first sliding device and the second sliding device. The first front mold core, the second front mold core, the first slider and the second slider are cooperatively arranged above the rear mold core. The cavity surrounded by the first front mold core, the second front mold core, the first slider, the second slider and the rear mold core forms an injection runner. A gate is arranged on the second front mold core.

[0008] Further, the first front mold core includes a mold core body, a left pipe orifice mold core and a right pipe orifice mold core. An installation through hole communicating the left and right side surfaces is arranged in the mold core body. The left pipe orifice mold core and the right pipe orifice mold core are both arranged in the installation through hole and are respectively fixed and positioned by a left positioning bolt and a right positioning bolt fixed on the side wall of the mold core body. Left and right operation through holes corresponding to the left pipe orifice mold core and the right pipe orifice mold core fixed in the installation through hole are opened on the top side of the mold core body. Left and right inclined through grooves corresponding to the left and right operation through holes are respectively opened in the left pipe orifice mold core and the right pipe orifice mold core.

[0009] Further, the auxiliary fixing system includes a thimble, a push block, a connecting rod, a fixed seat and a cylinder. The fixed seat is fixed to the side surface of the rear mold base. The cylinder is fixed through the fixed seat. The cylinder is fixed to the push block through the connecting rod. The push block is simultaneously fixed to the thimble and the mold core body. The thimble penetrates through the cavity surrounded by the left pipe orifice mold core and the right pipe orifice mold core fixed in the mold core body and is used for fixing the metal insert positioned on the positioning mechanism. A third chute is opened on the rear mold base. The third chute connects the fixed groove and the fixed seat. The cylinder drives the push block to perform linear reciprocating motion along the third chute.

[0010] Further, an indented "cross" groove is arranged at one end of the thimble extending into the injection cavity.

[0011] Further, the number of the positioning magnetic columns is three, namely a first positioning magnetic column, a second positioning magnetic column and a third positioning magnetic column.

[0012] Further, the number of the positioning dowel pins is two, namely a first positioning dowel pin and a second positioning dowel pin.

[0013] Further, the first positioning magnetic post, the second positioning magnetic post and the third positioning magnetic post are arranged in a straight line. The first positioning insert pin and the second positioning insert pin are respectively arranged on both sides of the middle second positioning magnetic post. The first positioning magnetic post, the second positioning magnetic post and the third positioning magnetic post are arranged in a cross shape with the first positioning insert pin and the second positioning insert pin.

[0014] The present invention also provides an injection molding method for manufacturing injection molded parts using the above injection mold, including the following steps:

[0015] Step S1, place a metal insert on the rear mold core fixed with the positioning mechanism, and limit and fix the metal insert through the positioning magnetic posts and positioning insert pins on the positioning mechanism;

[0016] Step S2, control the auxiliary fixing system to drive the first front mold core to be placed at a position matching the rear mold core;

[0017] Step S3, control the first sliding device and the second sliding device to drive the first slider and the second slider to move along the first chute and the second chute respectively to positions matching the first front mold core;

[0018] Step S4, control the second front mold core to be placed at a position matching the first slider system, the second slider system and the rear mold core;

[0019] Step S5, perform injection molding through the gate on the second front mold core;

[0020] Step S6, open the mold.

[0021] Advantages of the present invention:

[0022] The present invention provides an injection mold for manufacturing an automotive piston tube with a metal insert, including a rear mold base, a rear mold core, a front mold core, a positioning mechanism and an auxiliary fixing system. An inner concave fixing groove is provided on the rear mold base, and the rear mold core is fixed in the fixing groove. The front mold core is arranged above the rear mold core, and the space enclosed between the front mold core and the rear mold core forms an injection molding channel. A gate is provided on the front mold core. The positioning mechanism for limiting and fixing the metal insert is embedded in the rear mold core, and one end of the positioning mechanism extends into the rear mold cavity of the rear mold core. The auxiliary fixing system is arranged on the side of the rear mold base and is used to fix the metal insert positioned at one end of the positioning mechanism; the present invention also provides an injection molding method. The metal insert is limited and fixed by the positioning mechanism fixed on the rear mold core, then fixed by the auxiliary fixing system, and finally the rear mold core and the front mold core are clamped for injection molding. The present invention has the characteristics of simple structure, reliable positioning and convenient operation. Description of the Drawings

[0023] The present invention will be further described with reference to the accompanying drawings. However, the embodiments in the drawings do not constitute any limitation to the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the following drawings without creative efforts.

[0024] Figure 1 It is a schematic diagram of the overall structure when installing the front die carrier of an injection mold provided by the present invention.

[0025] Figure 2 It is a schematic diagram of the overall structure when removing the front die carrier of an injection mold provided by the present invention.

[0026] Figure 3 It is a schematic diagram of the partial structure when installing a metal insert on a positioning mechanism in an injection mold provided by the present invention.

[0027] Figure 4 It is in Figure 3 A sectional view taken along line E-E.

[0028] Figure 5 It is a schematic diagram of the structure of a positioning mechanism in an injection mold provided by the present invention.

[0029] Figure 6 It is a top view of the assembly of the rear mold core and the front mold core in an injection mold provided by the present invention.

[0030] Figure 7 It is in Figure 6 A sectional view taken along line A-A.

[0031] Figure 8 It is a schematic diagram of the front mold core of an injection mold provided by the present invention.

[0032] Figure 9 It is in Figure 8 A sectional view taken along line B-B.

[0033] Figure 10 It is a top view of an injection mold provided by the present invention.

[0034] Figure 11 It is in Figure 10 A sectional view taken along line C-C.

[0035] Figure 12 It is in Figure 10 A sectional view taken along line D-D. Detailed implementation manners

[0036] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0038] Refer to Figures 1 to 4 , this embodiment provides an injection mold for manufacturing an automotive piston tube with a metal insert, which includes a rear mold base 1, a rear mold core 2, a front mold core, a positioning mechanism 4, and an auxiliary fixing system 5. An inwardly concave fixing groove 11 is provided on the rear mold base 1, and the rear mold core 2 is fixed in the fixing groove 11. The front mold core is arranged above the rear mold core 2, and the space enclosed between the front mold core and the rear mold core 2 forms an injection runner. A gate is provided on the front mold core. The positioning mechanism 4 for limiting and fixing the metal insert 7 is embedded in the rear mold core 2. One end of the positioning mechanism 4 extends into the rear mold cavity of the rear mold core 2. The auxiliary fixing system 5 is arranged on the side of the rear mold base 1 and is used to fix the metal insert 7 positioned at one end of the positioning mechanism 4.

[0039] It should be noted that for the positioning mechanism 4 embedded in the rear mold core 2, its first end is flush with the bottom surface of the rear mold core 2 and abuts against the fixing groove 11 of the rear mold base 1 in a surface contact manner to prevent the positioning mechanism 4 from being unstably fixed. The second end protrudes from the bottom surface of the rear mold cavity of the rear mold core 2 and extends into the space of the rear mold cavity. Since the metal insert 7 is fixed to the second end of the positioning mechanism 4, the metal insert 7 is at a certain distance from the bottom surface of the rear mold cavity, which is convenient for manufacturing an injection molded part with plastic material wrapping the metal material. The auxiliary fixing system 5 provides auxiliary fixation for the metal insert 7 by implementing limitation on the inside of the metal insert 7. Combined with the limitation and fixation given by the positioning mechanism 4 from the outer surface of the metal insert 7, it provides double guarantee for the fixation of the metal insert 7, and has the characteristics of simple structure, reliable positioning, and convenient operation.

[0040] Refer to Figure 5, in this embodiment, the positioning mechanism 4 includes a positioning insert 41, three positioning magnetic posts for magnetically fixing the metal insert 7, and two positioning pins for cooperating with and fixing the limiting holes of the metal insert 7. The positioning magnetic posts are respectively the first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44, and the positioning pins are respectively the first positioning pin 45 and the second positioning pin 46; a step hole for fixing the insert is provided in the rear mold core 2, and the step hole for fixing the insert includes a sunken hole for fixing the insert and a through hole for fixing the insert. The first end face of the positioning insert 41 is clamped in the sunken hole for fixing the insert and is flush with the lower bottom surface of the rear mold core 2. The second end face of the positioning insert 41 passes through the through hole for fixing the insert and extends into the space of the rear mold cavity; a step hole for fixing the magnetic post is provided in the positioning insert 41, and the step hole for fixing the magnetic post includes a sunken hole for fixing the magnetic post and a through hole for fixing the magnetic post. The first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44 are respectively arranged in the sunken hole for fixing the magnetic post. The through hole for fixing the magnetic post communicates the sunken hole for fixing the magnetic post and the first end face of the positioning insert 41, and one end face of the first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44 installed in the sunken hole for fixing the magnetic post is flush with the second end face of the positioning insert 41; a step hole for fixing the pin is further provided in the positioning insert 41, and the step hole for fixing the pin includes a sunken hole for fixing the pin and a through hole for fixing the pin. The first ends of the first positioning pin 45 and the second positioning pin 46 are respectively clamped in the corresponding sunken holes for fixing the pin, and the second ends protrude from the second end face of the positioning insert 41 through the corresponding through holes for fixing the pin.

[0041] It should be noted that the first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44 are installed in the sunken hole for fixing the magnetic post, flush with the second end face of the positioning insert 41 to form a surface, and contact the outer wall surface of the metal insert 7 in a surface contact manner, and use magnetic attraction to hold the metal insert 7; in addition, the first positioning pin 45 and the second positioning pin 46 respectively extend from the corresponding sunken holes for fixing the pin. When the first ends of the first positioning pin 45 and the second positioning pin 46 are clamped into the corresponding sunken holes for fixing the pin, the second ends of the first positioning pin 45 and the second positioning pin 46 protrude from the second end face of the positioning insert 41, cooperate with the limiting through holes provided on the metal insert 7, and position the metal insert 7. Through the magnetic attraction positioning of the positioning magnetic posts and the positioning of the positioning pins and the limiting through holes respectively, the fixing reliability of the positioning mechanism 4 for the metal insert 7 is further improved.

[0042] Additionally, as one of the preferred solutions, the first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44 are arranged in a straight line. The first positioning insert pin 45 and the second positioning insert pin 46 are respectively arranged on both sides of the central second positioning magnetic post 43. The first positioning magnetic post 42, the second positioning magnetic post 43, and the third positioning magnetic post 44 and the first positioning insert pin 45 and the second positioning insert pin 46 are arranged in a cross shape. In this solution, for the tubular metal insert, the three positioning magnetic posts are arranged along the circumferential direction of the outer wall of the tubular metal insert, and the positioning insert pins are arranged along the central axis direction of the tubular metal insert, effectively preventing the rotation of the tubular metal insert and fixing the tubular metal insert more effectively.

[0043] Referring to Figures 6 to 12 , in this embodiment, the front mold core includes a first front mold core 31, a second front mold core 32, a first slider system 33, and a second slider system 34. The second front mold core 32 is fixed to the front mold base 6, the first front mold core 31 is fixed by an auxiliary fixing system 5. The first slider system 33 includes a first slider 331 and a first sliding device 332, the second slider system 34 includes a second slider 341 and a second sliding device 342. The first slider system 33 and the second slider system 34 are both fixed on the rear mold base 1. The rear mold base 1 is provided with a first chute 12 and a second chute 13 for the first slider 331 and the second slider 341 to slide respectively. The first slider 331 and the second slider 341 slide along the first chute 12 and the second chute 13 respectively driven by the first sliding device 332 and the second sliding device 342. The first front mold core 31, the second front mold core 32, the first slider 331, and the second slider 341 are cooperatively arranged above the rear mold core 2. The cavity surrounded by the first front mold core 31, the second front mold core 32, the first slider 331, the second slider 341 and the rear mold core 2 forms an injection runner, and a gate 321 is provided on the second front mold core 32.

[0044] Referring to Figures 8 to 9 , wherein, the first front mold core 31 includes a mold core body 311, a left pipe orifice mold core 312, and a right pipe orifice mold core 313. An installation through hole 314 communicating the left and right side surfaces is arranged in the mold core body 311. The left pipe orifice mold core 312 and the right pipe orifice mold core 313 are both arranged in the installation through hole 314 and are respectively fixed and positioned by a left positioning bolt and a right positioning bolt fixed on the side wall of the mold core body 311. The top side of the mold core body 311 is provided with a left operation through hole 315 and a right operation through hole 316 corresponding to the left pipe orifice mold core 312 and the right pipe orifice mold core 313 fixed in the installation through hole 314. Left inclined through grooves 317 and right inclined through grooves 318 corresponding to the left operation through hole 315 and the right operation through hole 316 are respectively arranged in the left pipe orifice mold core 312 and the right pipe orifice mold core 313.

[0045] It should be noted that the first front mold core 31, the second front mold core 32, the first slider system 33 and the second slider system 34 cooperate with each other to jointly form the front mold core. The lower sides of the first slider 331 and the second slider 341 are provided with clamping seats, which are respectively clamped and matched with the first chute 12 and the second chute 13 on the rear mold base 1, preventing the first slider 331 and the second slider 341 from directly disengaging from the rear mold base 1 from above, and ensuring that the first slider 331 and the second slider 341 can only move along the first chute 12 and the second chute 13 driven by the first sliding device 332 and the second sliding device 342; additionally, in order to injection mold the inclined installation plane of the automotive piston tube 8, the first front mold core 31 is matched with the first slider 331 and the second slider 341 through an inclined plane; in order to better complete the injection molding of the nozzle of the automotive piston tube 8, the first front mold core 31 is further provided with a left nozzle mold core 312 and a right nozzle mold core 313. The left nozzle mold core 312 and the right nozzle mold core 313 are respectively pushed in from both sides of the installation through hole 314. After reaching the set position, they are fixed and positioned by the left positioning bolt and the right positioning bolt fixed on the side wall of the mold core body 311. A cavity for injection molding the nozzle of the automotive piston tube 8 is formed between the fixed left nozzle mold core 312 and right nozzle mold core 313, and the left inclined through groove 317 and the right inclined through groove 318 can be directly touched through the left operation through hole 315 and the right operation through hole 316 on the top side of the mold core body 311. Applying force to the left inclined through groove 317 and the right inclined through groove 318 can realize the combination and separation of the left nozzle mold core 312 and the right nozzle mold core 313, providing an operation window and making the operation more convenient.

[0046] Referring to Figures 10 to 12 , in this embodiment, the auxiliary fixing system 5 includes a thimble 51, a push block 52, a connecting rod 53, a fixed seat 54 and a cylinder 55. The fixed seat 54 is fixed on the side of the rear mold base 1. The cylinder 55 is fixed through the fixed seat 54. The cylinder 55 is fixed to the push block 52 through the connecting rod 53. The push block 52 is simultaneously fixed to the thimble 51 and the mold core body 311. The thimble 51 is disposed through the cavity formed by the left nozzle mold core 312 and the right nozzle mold core 313 fixed in the mold core body 311 and is used to fix the metal insert 7 positioned on the positioning mechanism 4. A third chute 14 is formed on the rear mold base 1. The third chute 14 connects the fixed groove 11 and the fixed seat 54. The cylinder 55 drives the push block 52 to perform a linear reciprocating motion along the third chute 14.

[0047] It should be noted that the core body 311 is fixed on the ejector block 52 in advance, and the left nozzle core 312 and the right nozzle core 313 are fixed in the core body 311. At the same time, the ejector pin 51 is also fixed on the ejector block 52. The ejector pin 51 passes through the cavity surrounded by the left nozzle core 312 and the right nozzle core 313 and directly reaches the cavity of the second front core 32. Driven by the air cylinder 55, the ejector block 52 makes a linear reciprocating motion along the third chute 14 between the fixed seat 54 and the rear core 2, realizing the mold opening and closing movements of the first front core 31.

[0048] In addition, the end of the ejector pin 51 extending into the injection cavity is provided with an indented "cross" groove 56 to facilitate the injection molding of the structure of the closed end of the automotive piston tube 8.

[0049] The present invention also provides an injection molding method for manufacturing injection molded parts using the above injection mold, including the following steps:

[0050] Step S1, place the metal insert 7 on the rear core 2 fixed with the positioning mechanism 4, and limit and fix the metal insert 7 through the positioning magnetic column and the positioning insert on the positioning mechanism 4;

[0051] Step S2, control the auxiliary fixing system 5 to drive the first front core 31 to be placed at a position matching the rear core 2;

[0052] Step S3, control the first sliding device 332 and the second sliding device 342 to drive the first slider 331 and the second slider 341 to move along the first chute 12 and the second chute 13 respectively to positions matching the first front core 31;

[0053] Step S4, control the second front core 32 to be placed at a position matching the first slider system 33, the second slider system 34 and the rear core 2;

[0054] Step S5, perform injection molding through the gate 321 on the second front core 32;

[0055] Step S6, open the mold.

[0056] In this embodiment, during the mold closing process, the metal insert 7 is first placed on the positioning mechanism 4, and then the auxiliary fixing system 5 is controlled, the cylinder 55 pushes the push block 52 and then drives the first front mold core 31 to move along the direction of the third slide groove 14 to the top of the rear mold core 2, and at the same time, the ejector pin 51 fixed at the push block 52 passes through the inside of the circular tubular metal insert to perform a second limit fixation on the metal insert 7, and then the first slider 331 and the second slider 341 are controlled to move along the first slide groove 12 and the second slide groove 13 to the position matching the first front mold core 31, and the first front mold core 31 is clamped and fixed from the left and right sides, and then the front mold frame 6 is controlled to descend, and at the same time At the same time, the second front mold core 32 fixed on the front mold frame 6 descends to a position coordinated with the first slider system 33, the second slider system 34 and the rear mold core 2. At this point, a closed cavity is formed between the first front mold core 31, the second front mold core 32, the first slider 331, the second slider 341 and the rear mold core 2, and then injection molding is performed through the gate 321 on the second front mold core 32. After injection molding, the mold is opened. The mold opening order is to open the second front mold core 32 first, then open the rear mold core 2, open the first slider 331 and the second slider 341 at the same time, and finally pull out the first front mold core 31. At this point, the injection molded part is sleeved on the ejector pin 51. After it is taken down manually, the next cycle can be performed.

[0057] Compared with the prior art, the present embodiment provides an injection mold for preparing an automobile piston tube with a metal insert, comprising a rear mold frame 1, a rear mold core 2, a front mold core, a positioning mechanism 4 and an auxiliary fixing system 5. The rear mold frame 1 is provided with an inwardly concave fixing groove 11, and the rear mold core 2 is fixed in the fixing groove 11. The front mold core is arranged above the rear mold core 2, and the space enclosed by the front mold core 2 forms an injection flow channel. A gate is arranged on the front mold core, and the positioning mechanism 4 for limiting and fixing the metal insert 7 is embedded in the rear mold core 2, and one end of the positioning mechanism 4 extends into the rear mold cavity of the rear mold core 2. The auxiliary fixing system 5 is arranged on the side of the rear mold frame 1 and is used to fix the metal insert 7 positioned at one end of the positioning mechanism 4; the present invention also provides an injection molding method, wherein the metal insert 7 is limited and fixed by the positioning mechanism 4 fixed on the rear mold core 2, and then the metal insert 7 is fixed by the auxiliary fixing system 5, and finally the rear mold core 2 and the front mold core are molded together for injection molding. The invention has the characteristics of simple structure, reliable positioning and convenient operation.

[0058] Finally, it should be emphasized that the present invention is not limited to the above-mentioned implementation mode. The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An injection mold for manufacturing an automotive piston tube with a metal insert, characterized in that, it includes a rear mold base, a rear mold core, a front mold core, a positioning mechanism and an auxiliary fixing system. A concave fixing groove is provided on the rear mold base, and the rear mold core is fixed in this fixing groove. The front mold core is arranged above the rear mold core, and the space enclosed between the front mold core and the rear mold core forms an injection molding runner. A gate is provided on the front mold core. The positioning mechanism for limiting and fixing the metal insert is embedded in the rear mold core. One end of the positioning mechanism extends into the rear mold cavity of the rear mold core. The auxiliary fixing system is arranged on the side of the rear mold base and is used to fix the metal insert positioned at one end of the positioning mechanism; The positioning mechanism includes a positioning insert block, at least one positioning magnetic column for magnetically fixing the metal insert, and at least one positioning insert pin for cooperating with the limiting hole of the metal insert for fixing. The first end face of the positioning insert block embedded in the rear mold core is flush with the lower bottom face of the rear mold core. The positioning magnetic column is arranged on the second end face of the positioning insert block. The positioning insert pin extends from the first end face of the positioning insert block and one end of it protrudes from the second end face of the positioning insert block; The front mold core includes a first front mold core, a second front mold core, a first slider system and a second slider system. The second front mold core is fixed to the front mold base. The first front mold core is fixed through the auxiliary fixing system. The first slider system includes a first slider and a first sliding device. The second slider system includes a second slider and a second sliding device. Both the first slider system and the second slider system are fixed on the rear mold base. The rear mold base is provided with a first chute and a second chute for the first slider and the second slider to slide respectively. The first slider and the second slider slide along the first chute and the second chute respectively driven by the first sliding device and the second sliding device. The first front mold core, the second front mold core, the first slider and the second slider are cooperatively arranged above the rear mold core. The cavity enclosed between the first front mold core, the second front mold core, the first slider, the second slider and the rear mold core forms an injection molding runner. A gate is provided on the second front mold core; The first front mold core includes a mold core body, a left pipe orifice mold core and a right pipe orifice mold core. An installation through hole communicating the left and right side faces is provided in the mold core body. The left pipe orifice mold core and the right pipe orifice mold core are both arranged in this installation through hole and are respectively fixed and positioned by a left positioning bolt and a right positioning bolt fixed on the side wall of the mold core body. Left operation through holes and right operation through holes corresponding to the left pipe orifice mold core and the right pipe orifice mold core fixed in the installation through hole are opened on the top side of the mold core body. Left inclined through grooves and right inclined through grooves corresponding to the left operation through holes and the right operation through holes are respectively opened in the left pipe orifice mold core and the right pipe orifice mold core; The auxiliary fixing system includes a thimble, a pushing block, a connecting rod, a fixing seat and a cylinder. The fixing seat is fixed on the side of the rear mold base. The cylinder is fixed through the fixing seat. The cylinder is fixed to the pushing block through the connecting rod. The pushing block is simultaneously fixed to the thimble and the mold core body. The thimble is disposed through the cavity formed by the left nozzle mold core and the right nozzle mold core fixed in the mold core body and is used to fix the metal insert positioned on the positioning mechanism. A third chute is formed on the rear mold base. The third chute connects the fixing groove and the fixing seat. The cylinder drives the pushing block to perform linear reciprocating motion along the third chute.

2. An injection mold according to claim 1, wherein, a recessed "cross" groove is provided at one end of the thimble extending into the injection cavity.

3. An injection mold according to claim 1, wherein, the number of the positioning magnetic posts is three, namely a first positioning magnetic post, a second positioning magnetic post and a third positioning magnetic post respectively.

4. An injection mold according to claim 3, wherein, the number of the positioning dowel pins is two, namely a first positioning dowel pin and a second positioning dowel pin respectively.

5. An injection mold according to claim 4, wherein, the first positioning magnetic post, the second positioning magnetic post and the third positioning magnetic post are arranged in a straight line. The first positioning dowel pin and the second positioning dowel pin are respectively arranged on both sides of the central second positioning magnetic post. The first positioning magnetic post, the second positioning magnetic post and the third positioning magnetic post and the first positioning dowel pin and the second positioning dowel pin are arranged in a cross shape.

6. An injection method for manufacturing injection molded parts by using the injection mold according to any one of claims 1-2, wherein, it includes the following steps: Step S1, placing a metal insert on the rear mold core fixed with the positioning mechanism, and limiting and fixing the metal insert through the positioning magnetic posts and positioning dowel pins on the positioning mechanism; Step S2, controlling the auxiliary fixing system to drive the first front mold core to be placed at a position matching the rear mold core; Step S3, controlling the first sliding device and the second sliding device to drive the first slider and the second slider to move along the first chute and the second chute respectively to positions matching the first front mold core; Step S4, controlling the second front mold core to be placed at a position matching the first slider system, the second slider system and the rear mold core; Step S5, performing injection through the gate on the second front mold core; Step S6, opening the mold.

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