Ox horn pouring gate demolding method and demolding jig of glass fiber-containing plastic ox horn injection molding mold

Abstract

The invention discloses a horn gate demolding method and a demolding jig of a glass fiber plastic horn injection molding mold, and relates to the field of plastic injection molds.According to the horn gate demolding method of the glass fiber plastic horn injection molding mold, a horn material head is subjected to injection molding when the upper cavity wall and the lower cavity wall of a horn gate tunnel are closed; the size of the ox horn stub bar in the vertical direction is smaller than the size of the ox horn tunnel formed after the ox horn tunnel movable insert moves downwards, so that the bent hook part of the ox horn stub bar has more moving space when the ox horn stub bar is demolded, and glass fiber-containing plastic with poor plastic deformation performance and toughness is subjected to injection molding in an ox horn gate mode; by the adoption of the technical scheme, the problem that the sprue is blocked due to the fact that the stub bar is broken when the ox horn stub bar is hard dragged out of a bent tunnel can be avoided, the problem that the sprue is blocked due to the fact that a dehydration opening stub bar hook is internally broken after PC plastic with the glass fiber proportion being 20%-55% is subjected to injection molding in an ox horn sprue mode can be effectively solved, and the stable and efficient injection molding effect can be achieved.

Description

Technical Field

[0001] The invention relates to the field of plastic injection molds, and in particular to a method for demoulding a horn gate of a glass fiber-containing plastic horn injection molding mold and a demoulding jig. Background Art

[0002] After a certain proportion of glass fiber is mixed into engineering plastics, the hardness of the injection molded product can be effectively improved, thereby improving the strength performance of the product. However, the material head produced by the runner and gate as the injection channel will also become harder and more brittle. When dragged in a curved tunnel-type gate, it is easy to break and remain in the tunnel to block the gate, thus hindering the next cycle of injection molding. Because the toughness of mixed plastics with a high proportion of glass fiber is relatively poor, this kind of glass fiber plastic injection molding mold generally does not adopt latent (such as Figure 1 As shown) or bull horn type gate for injection molding.

[0003] like Figure 2 The following is a schematic diagram of the surface requirements of the background product of this application, and the gate design requirements of the mold:

[0004] First, the gap in the glue injection should not affect the appearance of the product. Figure 3 and Figure 4 If the gate is as shown, there will be gaps and cross-sections in the gate area, which will affect the appearance of the product. Figure 4 The side gate shown not only affects the peripheral appearance of the product, but also the post-process of the gate removal. The gate removal residue will also affect the product assembly sealing performance;

[0005] Second, the gate position should not affect the realization of other functional area structures inside the product, such as audio, antenna, PCB board, vibration motor and card slot;

[0006] Third, the gate design has no post-process or the post-process is as short as possible to avoid unnecessary increase in process costs. Figure 5 The latent injection method shown in the figure does not have high-face side walls or high-face ribs suitable for latent gate casting. Therefore, it is necessary to design an additional drainage plate connected to the latent gate based on the customer's product to realize the latent injection molding of the mold. In that case, not only the injection pressure loss is large, the product size and shrinkage problems are difficult to debug and solve, and the gate drainage plate cannot be automatically removed during the mold injection process. It needs to be removed by a special sprue cutting fixture, which increases the product post-process and has the risk of increasing the product output cycle time and producing more defective products. Therefore, the latent injection is not only costly, but also the injection effect is not ideal.

[0007] Without considering that the fiberglass plastic is hard and brittle, and has insufficient plastic deformation and toughness, forced dragging is likely to cause the hook to bend at the point with the greatest resistance (such as Figure 6 When there is a problem of fracture (the actual breakpoint in the process shown in the figure), for the background product, it is best to use a bull horn gate. First, the bull horn gate injection molding does not affect the appearance of the product; secondly, the bull horn gate injection molding is easier to design the gate at a more balanced position in the mold cavity relative to other injection methods without affecting the structure of other functional areas of the product (such as Figure 7 As shown); the bull horn gate can be automatically installed in the mold manufacturing process Figure 6 The design theoretical breakpoint is broken during the ejection process of the horn head by the ejection system of the mold. The gate residue after breaking is small, and the product can meet the assembly requirements.

[0008] In general, the bull horn gate has many advantages, such as it does not affect the appearance of the product, the location is easy to choose, the glue is evenly fed, the injection pressure loss is small, there is no post-process, the product output cycle is short and the product yield is high.

[0009] Therefore, the mold gate design of our products adopts the following Figure 8 The bull horn gate is shown in the figure, but its injection molding material is PC material mixed with 40% glass fiber. During the mold trial and trial production, we found the following problems:

[0010] If the gate head breakpoint of each injection molding cycle is Figure 6 The "design theory breakpoint" shown can meet the design requirements;

[0011] Usually the plastic (unmixed with glass fiber) horn head can be dragged out in a curved tunnel with a perfect fit (such as Fig. 9 As shown in the figure, the plastic is still at a certain mold temperature and has good soft plasticity and toughness. It can be dragged and follow the bending shape of the horn cavity to complete the demoulding of the horn gate;

[0012] However, when a certain proportion of glass fiber is mixed in it, the soft plasticity and toughness are obviously deteriorated. If it is still forcibly dragged in the conventional bullhorn tunnel, the actual gate head breakpoint frequently appears in the following places: Figure 6 The “actual breakpoint in the process” shown here forces the process to be interrupted to clean the gate channel, so the mold cannot be mass-produced normally. Summary of the invention

[0013] The purpose of the present invention is to provide a method for demolding a bull horn gate of a bull horn injection molding mold for glass fiber-containing plastics, which is used to solve the technical problem in the prior art that the dehydration port material head bend hook breaks and blocks the gate after injection molding of PC plastic containing 20% ​​to 55% of glass fiber using the bull horn gate method.

[0014] In order to achieve the above object, the present invention adopts the following technical solutions:

[0015] A method for demoulding a horn gate of a glass fiber-containing plastic horn injection molding mold comprises the following steps:

[0016] Step 1: Align the two product cavities on the front inner mold with the two product cavities on the rear inner mold, and then move the front inner mold downward;

[0017] Step 2: The front inner mold moving downward drives the two movable tunnel mechanisms in the rear inner mold to perform the contraction of the horn tunnel, so that the upper end surface of the tunnel movable insert in the movable tunnel mechanism and the upper half of the horn tunnel on the rear inner mold form a complete horn tunnel, thereby completing the mold closing of the front inner mold and the rear inner mold;

[0018] Step 3: Injection molding into the product cavity of the front inner mold and the product cavity of the rear inner mold through the complete horn tunnel;

[0019] Step 4: When the mold is opened, the two movable tunnel mechanisms automatically expand the horn tunnel, so that the distance between the upper end surface of the tunnel movable insert and the upper half of the horn tunnel on the rear inner mold increases;

[0020] Step 5: The mold ejection system synchronously pushes the product ejector pin and the runner ejector pin to gradually push the product and the bull horn gate sprue out of the product cavity and the bull horn tunnel respectively. The product and the bull horn gate sprue are disconnected at point A, where point A is the smallest gate between the product and the bull horn gate sprue;

[0021] Step 6: Use the robot to take away the product and the horn gate sprue;

[0022] Step 7: Reset the mold ejector system;

[0023] Step 8. The front inner mold is closed and the bull horn gate tunnel completes the closing action.

[0024] Preferably, in step two, the front inner mold moving downward will gradually contact the reset block in the movable tunnel mechanism, and the bottom surface of the reset block moving downward will fit with the two obtuse-angled surfaces on the tilting pressure block 6. The pressing force of the main parting surface on the reset block causes the tilting pressure block to rotate, thereby causing the bottom surface of the insert of the tunnel movable insert in the movable tunnel mechanism to move upward and maintain a supporting effect on the tunnel movable insert. The tension spring is pressed by the upper cavity wall of the spring cavity of the rear inner mold and the insert hanging platform, and the tension spring maintains a downward tensioning force on the tunnel movable insert. At this time, the upper end surface of the tunnel movable insert and the upper half of the bull horn tunnel on the rear inner mold form a complete bull horn tunnel, and the upper and lower parts of the bull horn tunnel are in a seamless fit state, so that the movable tunnel mechanism completes the tightening action of the bull horn tunnel.

[0025] Preferably, in step four, when the mold is opened, the tunnel movable insert is displaced downward under the elastic force of the tension spring, and synchronously pushes the tilting block and the rotating shaft to rotate, the obtuse surface of the tilting block tilts up and pushes the reset block to gradually pop out following the opening pace of the front inner mold, until the expansion limit surface of the reset block fits with the upper surface of the pressure plate, at this time, the tilting block has rotated 25°, and the movable tunnel mechanism completes the expansion action of the bull horn tunnel; in step eight, when the front inner mold is closed, the main parting surface presses against the top surface of the reset block, and performs a pressure reset action on the reset block. During this process, the main parting surface presses the reset block to move downward, and the bottom surface of the reset block presses the left end reset rolling surface of the tilting block, forcing the tilting block to rotate 25° around the rotating shaft, and the closing limit surface is fitted to the upper surface of the pressure plate, and the closing support surface on the right side of the tilting block tilts up to support the movable insert of the bull horn tunnel, and the tension spring is compressed again, so that the bull horn gate tunnel completes the closing action.

[0026] A demoulding jig for a horn gate of a glass fiber-containing plastic horn injection molding, comprising a movable tunnel mechanism and a tunnel movable insert: the movable tunnel mechanism comprises: a tunnel movable insert, which is arranged in a rear inner mold and is slidably connected to the rear inner mold, and the upper end surface of the tunnel movable insert matches the upper half of the horn tunnel on the rear inner mold; a rebound component, which is installed on the side of the tunnel movable insert; a pressure plate, which is installed in the rear inner mold and is located directly below the tunnel movable insert; a tilting pressure block, which is located between the tunnel movable insert and the pressure plate, and is rotatably connected to the rear inner mold, and the tilting pressure block One side of the top surface of the block is in contact with the movable insert of the tunnel; the bottom surface of the reset block is in contact with one side of the top surface of the movable insert of the tunnel; wherein, when the front inner mold and the rear inner mold are closed, when the reset block moves downward, the pressure block rotates and pushes the movable insert of the tunnel to move upward, the rebound component is compressed, and the upper end surface of the movable insert of the tunnel and the upper half of the horn tunnel on the rear inner mold form a complete horn tunnel; when the front inner mold and the rear inner mold are opened, the rebound component pushes the movable insert of the tunnel to move downward, and the distance between the upper end surface of the movable insert of the tunnel and the upper half of the horn tunnel increases.

[0027] Preferably, the movable tunnel insert comprises: an insert bottom surface; and an insert hanging platform fixedly connected to one side of the movable tunnel insert.

[0028] Preferably, the tilting pressure block includes: a rotating shaft, which is installed through the tilting pressure block and is rotatably connected to the rear inner mold; a closing limit surface, which is arranged on one side of the bottom of the tilting pressure block, and when the mold is closed, the closing limit surface is in contact with the top surface of the pressure plate; an extension limit surface, which is arranged on the other side of the bottom of the tilting pressure block, and when the mold is opened, the extension limit surface is in contact with the top surface of the pressure plate; a reset rolling surface, which is arranged on one side of the top of the tilting pressure block, and when the mold is opened, the reset rolling surface is in contact with the bottom surface of the reset block; a closing support surface, which is arranged on the other side of the top of the tilting pressure block, and when the mold is closed, the closing support surface is in contact with the bottom surface of the insert; an obtuse surface, which is arranged on the top of the tilting pressure block, located between the reset rolling surface and the closing support surface, and when the mold is closed, the obtuse surface is in contact with the bottom surface of the reset block.

[0029] Preferably, the rebound component is a tension spring, and the tension spring is installed on the top surface of the insert hanging platform.

[0030] Preferably, the maximum angle between the closed limit surface and the pressure plate is 25°, the maximum angle between the extended limit surface and the pressure plate is 25°, and the maximum moving distance of the tunnel movable insert is 25 mm.

[0031] Preferably, a plurality of fastening screws are provided on the pressing plate, and the fastening screws are connected to the rear inner mold.

[0032] Preferably, the upper horn tunnel on the rear inner mold is connected to the product cavity on the rear inner mold.

[0033] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0034] 1. The demoulding method of the bull horn gate of the glass fiber-containing plastic bull horn injection molding mold of the present invention is to perform injection molding of the bull horn head when the upper and lower cavity walls of the bull horn gate tunnel are closed, so that the upper and lower dimensions of the bull horn head are smaller than the upper and lower dimensions of the bull horn tunnel formed after the movable insert of the bull horn tunnel moves downward, so that the hook part of the bull horn head (the part most likely to break the head) has more activity space when it is demoulded, and can be dragged and lifted out in a loose space, so that the function of the bull horn injection molding tunnel changes from a fixed shape and size to a flexible opening and closing function. When the glass fiber-containing plastic with poor plastic deformation performance and toughness is injection molded by the bull horn gate method, the problem of the head breaking and blocking the gate when the bull horn head is pulled out of the curved tunnel can be avoided. The problem of the dehydration head hook breaking and blocking the gate after the PC plastic with a glass fiber ratio of 20% to 55% is injection molded by the bull horn gate method can be effectively solved, and the effect of stable and efficient injection molding can be achieved.

[0035] 2. The movable tunnel mechanism of the present invention is provided with a tunnel movable insert, a tension spring, a reset block, a tilting block, a rotating shaft and a pressure plate. When the mold is opened, the bull horn gate tunnel opens downward synchronously. When the bull horn head is ejected, its hook part has more room for movement, thereby avoiding the problem of the bull horn head with poor plastic deformation performance and toughness being forcibly dragged out of the curved tunnel to fit the mold tightly, causing the head to break and block the gate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of latent gate in the background technology of the present invention Figure 1 ;

[0037] Figure 2 It is a schematic diagram of the surface requirements of the background product in the present invention;

[0038] Figure 3 It is a schematic diagram of a pin-point gate in the background technology of the present invention;

[0039] Figure 4 It is a schematic diagram of the side gate in the background technology of the present invention;

[0040] Figure 5 Schematic diagram of latent gate in the background technology of the present invention Figure 2 ;

[0041] Figure 6 The breaking point of the horn head in the background technology of the present invention is shown in FIG. Figure 1 ;

[0042] Figure 7 It is a schematic diagram of the background product and the bull horn gate in the present invention;

[0043] Figure 8 The breaking point of the horn head in the background technology of the present invention is shown in FIG. Figure 2 ;

[0044] Fig. 9 It is a schematic diagram of the horn head being dragged along with the shape in the background technology of the present invention;

[0045] Fig.10 It is a top view of the assembly of the active mechanism of the ox-horn gate tunnel in the present invention;

[0046] Fig.11 It is an isometric view of the movable mechanism of the ox-horn gate tunnel in the present invention;

[0047] Fig.12 It is a right side view of the assembly of the tunnel movable mechanism in the present invention;

[0048] Fig.13 This is a front view of the assembly of the tunnel movable mechanism of the present invention;

[0049] Fig.14The position and shape change of the horn head being dragged and lifted off in the present invention Figure 1 ;

[0050] Fig.15 The position and shape change of the horn head being dragged and lifted off in the present invention Figure 2 ;

[0051] Fig.16 The position and shape change of the horn head being dragged and lifted off in the present invention Figure 3 ;

[0052] Fig.17 This is a diagram showing the deformation of the horn head after it is pushed away from the tunnel opening in the present invention;

[0053] Fig.18 A diagram showing the situation of the movable insert of the horn tunnel in the present invention being ready for reset;

[0054] Figure numerals: 1. product; 2. bull-horn gate head; 3. tunnel movable insert; 4. tension spring; 5. reset block; 6. pressure block; 7. rotating shaft; 8. pressure plate; 9. fastening screw; 10. runner ejector; 11. product ejector; 12. closing limit surface; 13. extension limit surface; 14. main parting surface; 15. obtuse surface; 16. insert bottom surface; 17. insert hanging platform; 18. travel limit surface; 19. reset rolling surface; 20. closing support surface. DETAILED DESCRIPTION

[0055] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments and drawings, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0056] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0057] Example

[0058] like Fig.10 - Fig.18 As shown, a method for demoulding a horn gate of a glass fiber-containing plastic horn injection molding mold comprises the following steps:

[0059] Step 1: Align the two product cavities on the front inner mold with the two product cavities on the rear inner mold, and then move the front inner mold downward;

[0060] Step 2: The front inner mold moving downward will gradually contact the reset block 5 in the movable tunnel mechanism, and the bottom surface of the reset block 5 moving downward will fit with the two obtuse surfaces 15 on the tilting pressure block 6. The pressing force of the main parting surface 14 on the reset block 5 causes the tilting pressure block 6 to rotate, thereby causing the insert bottom surface 16 of the tunnel movable insert 3 in the movable tunnel mechanism to move upward and maintain a supporting effect on the tunnel movable insert 3. The tension spring 4 is pressed by the upper cavity wall of the spring cavity of the rear inner mold and the insert hanging platform 17, and the tension spring 4 maintains a downward tension thrust on the tunnel movable insert 3. At this time, the upper end surface of the tunnel movable insert 3 and the upper half of the bull horn tunnel on the rear inner mold form a complete bull horn tunnel, and the upper and lower parts of the bull horn tunnel are in a seamless fitting state, so that the movable tunnel mechanism completes the tightening action of the bull horn tunnel, and then completes the mold closing of the front inner mold and the rear inner mold;

[0061] Step 3: Injection molding into the product cavity of the front inner mold and the product cavity of the rear inner mold through the complete horn tunnel;

[0062] Step 4: When the mold is opened, the tunnel movable insert 3 moves downward under the elastic force of the tension spring 4, and simultaneously pushes the tilting block 6 and the rotating shaft 7 to rotate. The obtuse surface 15 of the tilting block 6 tilts up and pushes the reset block 5 to gradually pop out following the mold opening pace of the front inner mold, until the hanging surface of the reset block 5 reaches the travel limit surface 18 (the function of this limit surface is to prevent it from falling out of the mold). At this time, the tilting block 6 has rotated 25°, and the movable tunnel mechanism completes the expansion action of the bull horn tunnel, so that the distance between the upper end surface of the tunnel movable insert 3 and the upper half of the bull horn tunnel on the rear inner mold is increased, and the current inner mold continues to open the mold to the maximum mold opening position (satisfying the mold opening distance for the manipulator to take away the product 1 and the bull horn gate head 2);

[0063] Step 5: The mold ejection system synchronously pushes the product ejector pin 11 and the runner ejector pin 10 to gradually push the product 1 and the horn gate sprue head 2 out of the product cavity and the horn tunnel respectively. The schematic diagram of the position and shape change of the horn sprue head during the process is shown in FIG. Fig.14 - Fig.17 As shown, the product 1 and the bull horn gate material head 2 are disconnected at A, wherein A is the smallest gate between the product 1 and the bull horn gate material head 2, and A can also be called the design breakpoint;

[0064] Step 6: Use a robot to take away the product 1 and the horn gate sprue 2;

[0065] Step 7: Reset the mold ejector system;

[0066] Step 8: When the front inner mold is closed, the main parting surface 14 is against the top surface of the reset block 5, and the reset block 5 is pressed and reset (such as Fig.18As shown in the figure, during this process, the main parting surface 14 presses the reset block 5 to move downward, and the bottom surface of the reset block 5 presses the left end reset rolling surface 19 of the tilting block 6, forcing the tilting block 6 to rotate 25° around the rotation axis 7, and the closing limit surface 12 is in contact with the upper surface of the pressure plate 8, and the right side of the tilting block 6 The closed support surface 20 is tilted to hold the active insert 3 of the horn tunnel, and the tension spring 4 is compressed again, so that the horn gate tunnel completes the closing action (as shown in the figure). Fig.12 and Fig.13 shown);

[0067] In step seven, the mold ejector system is used to eject the finished product from the mold during the mold opening process for subsequent processing or removal. The mold ejector system includes at least a hydraulic cylinder and an ejector. The extended end of the hydraulic cylinder is used to drive the ejector to move. The ejector matches the ejector hole on the mold. It is necessary to avoid the ejector and the ejector hole being too tight to cause jamming, and to avoid the ejector and the ejector hole being too loose to cause burrs.

[0068] Example 2

[0069] like Fig.10 - Fig.18 As shown, while other parts are the same as those of Example 1, the difference between this embodiment and Example 1 is that the movable tunnel mechanism includes a tunnel movable insert 3, a rebound assembly, a pressure plate 8, a tilting pressure block 6 and a reset block 5.

[0070] The tunnel movable insert 3 is arranged in the rear inner mold and is slidably connected to the rear inner mold. The upper end surface of the tunnel movable insert 3 matches the upper half of the bull horn tunnel on the rear inner mold; the rebound component is installed on the side of the tunnel movable insert 3; the pressure plate 8 is installed in the rear inner mold, and the pressure plate 8 is located directly below the tunnel movable insert 3.

[0071] The tilting pressure block 6 is located between the tunnel movable insert 3 and the pressure plate 8. The tilting pressure block 6 is rotatably connected to the rear inner mold. One side of the top surface of the tilting pressure block 6 contacts the tunnel movable insert 3; the bottom surface of the reset block 5 contacts one side of the top surface of the tunnel movable insert 3.

[0072] Specifically, when the front inner mold and the rear inner mold are closed, the front inner mold will push the reset block 5 to move downward, thereby causing the warping block 6 to rotate and push the tunnel movable insert 3 to move upward, thereby compressing the rebound component, so that the upper end surface of the tunnel movable insert 3 and the upper half of the bull horn tunnel on the rear inner mold form a complete bull horn tunnel; when the front inner mold and the rear inner mold are separated, the rebound component will push the tunnel movable insert 3 to move downward, and the distance between the upper end surface of the tunnel movable insert 3 and the upper half of the bull horn tunnel will increase.

[0073] The movable tunnel insert 3 comprises an insert bottom surface 16 and an insert hanging platform 17 . The insert hanging platform 17 is fixedly connected to one side of the movable tunnel insert 3 .

[0074] The tilting block 6 includes a rotating shaft 7 , a closing limit surface 12 , an extending limit surface 13 , a resetting rolling surface 19 , a closing support surface 20 and an obtuse angle surface 15 .

[0075] The rotating shaft 7 is installed on the tilting block 6 through and through, and the rotating shaft 7 is rotatably connected to the rear inner mold; the closing limit surface 12 is set on one side of the bottom of the tilting block 6, and when the mold is closed, the closing limit surface 12 is in contact with the top surface of the pressure plate 8; the extension limit surface 13 is set on the other side of the bottom of the tilting block 6, and when the mold is opened, the extension limit surface 13 is in contact with the top surface of the pressure plate 8; the reset rolling surface 19 is set on one side of the top of the tilting block 6, and when the mold is opened, the reset rolling surface 19 contacts with the bottom surface of the reset block 5; the closing support surface 20 is set on the other side of the top of the tilting block 6, and when the mold is closed, the closing support surface 20 contacts with the bottom surface 16 of the insert; the obtuse surface 15 is set on the top of the tilting block 6, located between the reset rolling surface 19 and the closing support surface 20, and when the mold is closed, the obtuse surface 15 contacts with the bottom surface of the reset block 5.

[0076] The rebound component is a tension spring 4, which is installed on the top surface of the insert hanging platform 17. The tension spring 4 is made of stainless steel. The stainless steel tension spring 4 can resist corrosion from air, steam, water, weak corrosive media such as acids, alkalis, salts, and chemically corrosive media, and is suitable for a variety of environments. The stainless steel tension spring 4 has high plasticity and fatigue resistance, so that the tension spring 4 can withstand multiple repeated loading and unloading without being easily damaged.

[0077] The maximum angle between the closed limit surface 12 and the pressing plate 8 is 25°, the maximum angle between the extended limit surface 13 and the pressing plate 8 is 25°, and the maximum moving distance of the tunnel movable insert 3 is 25mm. A plurality of fastening screws 9 are arranged on the pressing plate 8, and the fastening screws 9 are connected to the rear inner mold. The upper half of the bull horn tunnel on the rear inner mold is connected to the product cavity on the rear inner mold.

[0078] Working principle: in specific use, when the mold is closed, the front inner mold moving downward will gradually contact the reset block 5 in the movable tunnel mechanism, and the bottom surface of the reset block 5 moving downward will fit with the two obtuse surfaces 15 on the tilting block 6. The pressing force of the main parting surface 14 on the reset block 5 causes the tilting block 6 to rotate, thereby causing the insert bottom surface 16 of the tunnel movable insert 3 in the movable tunnel mechanism to move upward and maintain a supporting effect on the tunnel movable insert 3. The tension spring 4 is pressed by the upper cavity wall of the spring cavity of the rear inner mold and the insert hanging platform 17, and the tension spring 4 maintains a downward tensioning force on the tunnel movable insert 3. At this time, the upper end surface of the tunnel movable insert 3 and the upper half of the bull horn tunnel on the rear inner mold form a complete bull horn tunnel, and the upper and lower parts of the bull horn tunnel are in a seamless fit state, so that the movable tunnel mechanism completes the tightening action of the bull horn tunnel, and then completes the mold closing of the front inner mold and the rear inner mold.

[0079] When the mold is opened, the front inner mold will gradually move upward, and the tunnel movable insert 3 will move downward under the elastic force of the tension spring 4, and simultaneously push the tilting block 6 and the rotating shaft 7 to rotate. The obtuse surface 15 of the tilting block 6 will tilt up and push the reset block 5 to gradually pop out following the opening pace of the front inner mold. The movable tunnel mechanism completes the expansion action of the bull horn tunnel, so that the distance between the upper end face of the tunnel movable insert 3 and the upper half of the bull horn tunnel on the rear inner mold is increased.

[0080] Finally, the mold ejection system synchronously pushes the product ejector pin 11 and the runner ejector pin 10 to gradually push the product 1 and the bull-horn gate sprue 2 out of the product cavity and the bull-horn tunnel respectively. The product 1 and the bull-horn gate sprue 2 are disconnected at A, thereby completing the demolding of the product 1 and the bull-horn gate sprue 2.

[0081] The demoulding method of the gate of the glass fiber plastic horn injection molding mold is based on the technical problems encountered in our company's actual production. From the results of the trial mold process, it is a probability problem that the breakpoint appears at the "design breakpoint" or "actual breakpoint in the process" (the breakpoint is shown as follows Figure 6 ), indicating that the mixed plastic containing glass fiber still has the properties of thermo-soft plasticity, toughness and elastic deformation, but the performance is relatively poor when there is no mixed glass fiber. By designing a movable bull horn tunnel device that can open and close according to the injection and demolding timing of the mold, and conducting a large number of tests and verifications, using the data obtained from the experiments, the model design, parts manufacturing and assembly debugging are continuously optimized, and the technical method of the device is actually verified to be feasible and reliable. The technical method of the present application, which is summarized based on a large amount of trial and error and trial production experience, can actually effectively solve the problem of the dehydration port head bend hook breaking and blocking the gate after injection molding of PC plastics containing 20% ​​to 55% of glass fiber using the bull horn gate method.

[0082] Among them, the PC plastic mentioned above is polycarbonate, which is a high molecular polymer containing carbonate groups in the molecular chain; PC plastic has the advantages of high strength, high impact strength, good dimensional stability, small creep (very little change under high temperature conditions), high transparency and free dyeing. In addition, PC plastic also has good heat aging resistance and a wide range of operating temperatures. The enhanced UL temperature index reaches 120-140°C (it also has good outdoor long-term aging resistance). It also has excellent solvent resistance and no stress cracking.

[0083] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

[0084] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for demoulding a horn gate of a glass fiber-containing plastic horn injection molding mold, characterized in that: The steps include: Step 1: Align the two product cavities on the front inner mold with the two product cavities on the rear inner mold, and then move the front inner mold downward; Step 2: The front inner mold moving downward drives the two movable tunnel mechanisms in the rear inner mold to perform a contraction action on the horn tunnel, so that the upper end surface of the tunnel movable insert (3) in the movable tunnel mechanism and the upper half of the horn tunnel on the rear inner mold form a complete horn tunnel, thereby completing the mold closing of the front inner mold and the rear inner mold; Step 3: Injection molding into the product cavity of the front inner mold and the product cavity of the rear inner mold through the complete horn tunnel; Step 4: When the mold is opened, the two movable tunnel mechanisms automatically expand the horn tunnel, so that the distance between the upper end surface of the tunnel movable insert (3) and the upper half of the horn tunnel on the rear inner mold increases; Step 5: The mold ejection system synchronously pushes the product ejector pin (11) and the runner ejector pin (10) to gradually push the product (1) and the bullhorn gate sprue (2) out of the product cavity and the bullhorn tunnel respectively, and the product (1) and the bullhorn gate sprue (2) are disconnected at point A, wherein point A is the smallest gate of the product (1) and the bullhorn gate sprue (2); Step 6: Use a robot to take away the product (1) and the horn gate sprue (2); Step 7: Reset the mold ejector system; Step 8. The front inner mold is closed and the bull horn gate tunnel completes the closing action.

2. The method for demoulding the gate of a glass fiber-containing plastic horn injection molding mold according to claim 1, characterized in that: In step 2, the front inner mold moving downward will gradually contact the reset block (5) in the movable tunnel mechanism, and the bottom surface of the reset block (5) moving downward will fit with the two obtuse angle surfaces (15) on the tilting and pressing block (6). The pressing force of the main parting surface (14) on the reset block (5) causes the tilting and pressing block (6) to rotate, thereby causing the insert bottom surface (16) of the tunnel movable insert (3) in the movable tunnel mechanism to move upward and maintain a supporting effect on the tunnel movable insert (3). The tension spring (4) is pressed by the upper cavity wall of the spring cavity of the rear inner mold and the insert hanging platform (17). The tension spring (4) maintains a downward tension thrust on the tunnel movable insert (3). At this time, the upper end surface of the tunnel movable insert (3) and the upper half of the horn tunnel on the rear inner mold form a complete horn tunnel. The upper and lower parts of the horn tunnel are in a seamless fit state, so that the movable tunnel mechanism completes the tightening action of the horn tunnel.

3. The method for demoulding the gate of a glass fiber-containing plastic horn injection molding mold according to claim 1, characterized in that: In step 4, when the mold is opened, the tunnel movable insert (3) moves downward under the elastic force of the tension spring (4), and simultaneously pushes the tilting pressure block (6) and the rotating shaft (7) to rotate, and the obtuse surface (15) of the tilting pressure block (6) tilts up and pushes the reset block (5) to gradually pop out following the opening pace of the front inner mold until the expansion limit surface (13) of the reset block (5) fits with the upper surface of the pressure plate (8). At this time, the tilting pressure block (6) has rotated 25°, and the movable tunnel mechanism completes the expansion action of the bull horn tunnel; In step eight, when the front inner mold is closed, the main parting surface (14) presses against the top surface of the reset block (5), and performs a pressing and resetting action on the reset block (5). During this process, the main parting surface (14) presses the reset block (5) to move downward, and the bottom surface of the reset block (5) presses the left end reset rolling surface (19) of the tilting block (6), forcing the tilting block (6) to rotate 25° around the rotation axis (7), and the closing limit surface (12) is aligned with the upper surface of the pressure plate (8). The right side of the closed support surface (20) of the tilting block (6) is tilted to support the bull horn tunnel movable insert (3), and the tension spring (4) is compressed again, so that the bull horn gate tunnel completes the closing action.

4. A horn gate demoulding fixture for injection molding of glass fiber-containing plastic horns, characterized in that: It comprises a movable tunnel mechanism and a movable tunnel insert (3), wherein the movable tunnel mechanism comprises: A tunnel movable insert (3) is arranged in the rear inner mold and is slidably connected to the rear inner mold, and the upper end surface of the tunnel movable insert (3) matches the upper half of the horn tunnel on the rear inner mold; A rebound component is installed on the side of the tunnel movable insert (3); A pressing plate (8) is installed in the rear inner mold and is located directly below the tunnel movable insert (3); A warping and pressing block (6) is located between the tunnel movable insert (3) and the pressing plate (8), and is rotatably connected to the rear inner mold, and one side of the top surface of the warping and pressing block (6) is in contact with the tunnel movable insert (3); A reset block (5), the bottom surface of which is in contact with one side of the top surface of the tunnel movable insert (3); Among them, when the front inner mold and the rear inner mold are closed, when the reset block (5) moves downward, the pressure block (6) rotates and pushes the tunnel movable insert (3) to move upward, the rebound component is compressed, and the upper end surface of the tunnel movable insert (3) and the upper half of the horn tunnel on the rear inner mold form a complete horn tunnel; when the front inner mold and the rear inner mold are opened, the rebound component pushes the tunnel movable insert (3) to move downward, and the distance between the upper end surface of the tunnel movable insert (3) and the upper half of the horn tunnel increases.

5. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 4, characterized in that: The tunnel movable insert (3) comprises: Insert bottom surface (16); The insert hanging platform (17) is fixedly connected to one side of the tunnel movable insert (3).

6. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 4, characterized in that: The warping block (6) comprises: A rotating shaft (7) is installed through the tilting and pressing block (6) and is rotatably connected to the rear inner mold; A closing limit surface (12) is arranged on one side of the bottom of the warping and pressing block (6), and when the mold is closed, the closing limit surface (12) is in contact with the top surface of the pressing plate (8); An extended limiting surface (13) is arranged on the other side of the bottom of the warping pressure block (6), and when the mold is opened, the extended limiting surface (13) is in contact with the top surface of the pressing plate (8); A reset rolling surface (19) is arranged on one side of the top of the warping block (6), and when the mold is opened, the reset rolling surface (19) contacts the bottom surface of the reset block (5); A closed support surface (20) is arranged on the other side of the top of the warping block (6), and when the mold is closed, the closed support surface (20) contacts the bottom surface (16) of the insert; The obtuse-angled surface (15) is arranged on the top of the warping block (6) and is located between the resetting rolling surface (19) and the closing support surface (20). When the mold is closed, the obtuse-angled surface (15) contacts the bottom surface of the resetting block (5).

7. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 5, characterized in that: The rebound component is a tension spring (4), and the tension spring (4) is installed on the top surface of the insert hanging platform (17).

8. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 6, characterized in that: The maximum angle between the closed limit surface (12) and the pressure plate (8) is 25°, the maximum angle between the extended limit surface (13) and the pressure plate (8) is 25°, and the maximum moving distance of the tunnel movable insert (3) is 25 mm.

9. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 6, characterized in that: A plurality of fastening screws (9) are provided on the pressing plate (8), and the fastening screws (9) are connected to the rear inner mold.

10. The horn gate demoulding jig for glass fiber-containing plastic horn injection molding according to claim 4, characterized in that: The upper horn tunnel on the rear inner mold is communicated with the product cavity on the rear inner mold.

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