Mother-and-child screw injection molding device

Abstract

The present invention relates to a parent-child screw injection molding device, wherein a driving mechanism is slidably connected to a base, a barrel is fixedly connected to a barrel seat of the base, the barrel seat is slidably connected to the base, the barrel includes a front barrel and a rear barrel, one end of the screw is inserted into the barrel, and its end is detachably connected to a mother screw head, and the other end is transmission-connected to the driving mechanism, and a sub-screw head is installed on the mother screw head, and the sub-screw head cooperates with a pressurized inner cavity in the front barrel, or a secondary sub-screw head is installed at the front end of the sub-screw head, and the secondary sub-screw head cooperates with a pressurized inner cavity in the front barrel. The present invention adds a sub-screw head or even a secondary sub-screw head to the mother screw head, and can simultaneously obtain high pressure or ultra-high injection pressure under a large injection amount, greatly improve product quality, increase injection amount, shorten feeding time, improve production efficiency, reduce wear of the screw barrel, save electricity, and is also suitable for plastic products with particularly long feeding time, saving costs.

Description

Technical Field

[0001] The invention relates to an injection molding device, in particular to a parent-child screw injection molding device. Background Art

[0002] During the injection process of a traditional injection molding machine, since the mold cavity is empty at the beginning, the injection pressure only needs to be very low. When the injection reaches 60%-80%, the injection pressure needs to be slowly increased, and a very high injection pressure is required for the last 3%-10%. This last little bit is the most difficult to inject, and this is the stage where product defects such as material shortage and wall shrinkage are most likely to occur in the actual production process. When the injection molding machine is used to inject thick-walled plastic products and partially thick-walled plastic products, after the plastic is injected into the mold cavity, it is first cooled and solidified close to both sides of the mold, and then slowly cooled and solidified in the middle. Due to the large shrinkage rate of the plastic, a strong suction force is generated during the cooling in the middle, so there are two results: one is that the surface is concave (referred to as shrinkage) affecting the appearance, and the other is that a cavity appears in the middle to reduce the density and strength. The traditional injection molding machine The highest injection pressure of the injection molding machine is constant. It is impossible to meet the needs of each product one by one for different plastic raw materials and various plastic products. Therefore, the injection molding machine manufacturer provides three to four screws of different sizes for users to choose when accepting orders for each injection molding machine, but the quality and appearance of a considerable part of them are still not ideal. Injection pressure and injection volume are two very important indicators of injection molding machines. Injection pressure is related to product quality and whether qualified products can be made. The injection volume is related to how large the product can be processed to bring economic benefits to users. If you choose a large screw, the injection volume is large, but the injection pressure is small. On the contrary, if you choose a small screw, the injection pressure is large but the injection volume is small. In actual use, it also requires multiple debugging to achieve the best use effect, which is very troublesome. For some modified engineering plastics such as nylon plus glass fiber, polystyrene plus calcium carbonate, these materials have very large wear on the screw barrel. Sometimes a set of screw barrels needs to be replaced every few months, which is very troublesome and costly. Since the screw diameter is difficult to select, users usually choose a screw of medium size to take both ends into consideration. However, the injection volume will not be large, the injection pressure will not be very high, and future product changes will also be affected, making it inconvenient to use. Summary of the invention

[0003] The purpose of the present invention is to provide a parent-screw injection molding device, which can control the injection pressure while ensuring the injection volume, thereby greatly improving the product yield rate, greatly reducing the wear on the screw barrel, shortening the processing time, and sometimes allowing products that were originally to be processed on a larger injection molding machine to be processed on a smaller injection molding machine, thereby saving costs and being convenient to use.

[0004] In order to achieve the above-mentioned purpose, the technical solution of the present invention is: a parent-child screw injection molding device, comprising a base, a driving mechanism, a barrel and a screw, the driving mechanism is slidably connected to the base, the barrel is fixedly connected to the barrel seat of the base, the barrel seat is slidably connected to the base, the barrel comprises a front barrel and a rear barrel, the rear barrel is provided with a feed port, the barrel seat is equipped with a hopper and the position of the hopper corresponds to the position of the feed port, one end of the screw is inserted into the barrel, and its end is detachably connected to a mother screw head, and the other end is transmission-connected to the driving mechanism, and the improvement lies in: a child screw head is installed on the mother screw head, and the child screw head cooperates with the pressurized inner cavity in the front barrel, or a secondary child screw head is installed at the front end of the child screw head, and the secondary child screw head cooperates with the pressurized inner cavity in the front barrel.

[0005] In the above technical solution, a reflow groove is provided on the inner wall surface of the front barrel and / or the inner wall surface of the rear barrel, and the reflow groove is in a groove shape.

[0006] In the above technical solution, a reflux hole and a reflux channel are provided on the inner wall surface of the front barrel and / or the inner wall surface of the rear barrel, and the reflux channel is in a tunnel shape.

[0007] In the above technical solution, the front barrel has a reflux groove on its inner wall surface, and the rear barrel has a reflux hole and a reflux channel on its inner wall surface, and the reflux groove is in the shape of a groove, and the reflux channel is in the shape of a tunnel; or, the front barrel has a reflux hole and a reflux channel on its inner wall surface, and the rear barrel has a reflux groove on its inner wall surface, and the reflux groove is in the shape of a groove, and the reflux channel is in the shape of a tunnel.

[0008] In the above technical solution, the sub-screw head is threadedly connected to the female screw head, a female check ring is sleeved on the female screw head, and a check valve is provided on the outer wall surface of the front barrel.

[0009] In the above technical solution, the driving mechanism includes an injection cylinder, an oil motor, a cylinder seat and a driving seat. The driving seat is slidably connected to the base, the oil motor is fixedly connected to the driving seat, the cylinder seat is fixedly connected to the barrel seat or is integrated with the barrel seat, the outer end of the piston rod of the injection cylinder is fixedly connected to the driving seat, and the other end of the screw is transmission-connected to the oil motor.

[0010] In the above technical solution, the sub-screw head is threadedly connected to the female screw head, the female screw head is sleeved with a female check ring, and the sub-screw head is sleeved with a sub-check ring.

[0011] In the above technical solution, the sub-screw head is threadedly connected to the female screw head, a sub-check ring is mounted on the sub-screw head, a secondary sub-screw head is threadedly connected to the front end of the sub-screw head, and a secondary check ring is mounted on the secondary sub-screw head.

[0012] In the above technical solution, a female check ring is mounted on the female screw head.

[0013] In the above technical solution, the outer periphery of the front end of the sub-screw head has a pushing screw rib.

[0014] Since a sub-screw head is added to the mother screw head, and the sub-screw head located at the front end of the mother screw head is used to increase the injection pressure in the final stage, high pressure or ultra-high injection pressure can be obtained at the same time under the condition of large injection volume, which greatly improves product quality, increases injection volume, shortens feeding and processing time, improves production efficiency, saves electricity, reduces the wear of the screw barrel, and is also suitable for plastic products with particularly long feeding time. Sometimes, products that were originally to be processed on a larger injection molding machine can be processed on a smaller injection molding machine, which saves costs to a great extent and is easy to use. In addition, since it is difficult to select the screw diameter in the prior art, users generally choose a screw of an intermediate size to take both ends into consideration, but the injection volume will not be large and the injection pressure will not be very high. In the future, if the product needs to be changed, it will also be affected, which is very troublesome. If the present invention is used, this problem can be basically solved. When using a large screw, an ultra-high injection force can be obtained. If the injection pressure needs to be adjusted, it is only necessary to replace the front barrel and the sub-screw, which is also relatively convenient and easy. When using PP (polypropylene) and PE (polyethylene) with good fluidity, the injection volume can be increased by 50% or even more. For some modified engineering plastics such as nylon plus glass fiber, polystyrene plus calcium carbonate, these materials cause great wear on the screw barrel, and sometimes a set of screw barrels needs to be replaced every few months. By using the present invention, the mother screw is made into a special feeding and plasticizing screw, and the sub-screw is made into an injection screw, which can greatly reduce the wear on the screw barrel. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for describing the embodiments, wherein:

[0016] Figure 1 It is a three-dimensional schematic diagram of the present invention;

[0017] Figure 2 is a front cross-sectional schematic diagram of the present invention;

[0018] Figure 3 It is a stereoscopic diagram of the barrel and the screw in the present invention;

[0019] Figure 4 It is a schematic diagram of the main cross-section of the barrel and the screw in the present invention;

[0020] Figure 5 yes Figure 4 A magnified view of part I;

[0021] Figure 6 It is a front cross-sectional schematic diagram of a second embodiment of a barrel and a screw in the present invention;

[0022] Figure 7 yes Figure 6 The enlarged view of part II;

[0023] Figure 8 It is a front cross-sectional schematic diagram of a third embodiment of a barrel and a screw in the present invention;

[0024] Fig. 9 yes Figure 8 The enlarged view of part III;

[0025] Fig.10 is an enlarged view of a fourth embodiment of the barrel and the screw in the present invention;

[0026] Fig.11 It is a three-dimensional schematic diagram of another sub-screw head in the present invention;

[0027] Fig.12 is an enlarged view of a fifth embodiment of the barrel and the screw in the present invention;

[0028] Fig.13 is an enlarged view of a sixth embodiment of the barrel and the screw in the present invention;

[0029] Fig.14 is an enlarged view of a seventh embodiment of the barrel and the screw in the present invention;

[0030] Fig.15 It is an enlarged view of the eighth embodiment of the barrel and the screw in the present invention.

[0031] The components in the accompanying drawings are marked as follows: base 100; barrel seat 110; drive mechanism 200; injection cylinder 210; oil motor 220; cylinder seat 230; drive seat 240; barrel 300; front barrel 310; check valve 311; rear barrel 320; feed port 321; reflux groove 330; reflux hole 331; reflux channel 332; pressurized inner cavity 340; screw 400; female screw head 410; female check ring 411; sub-screw head 420; sub-check ring 421; push screw rib 422; secondary sub-screw head 430; secondary check ring 431; hopper 500; mold 600; moving cylinder 700. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] See also Figures 1 to 15 , the embodiment of the present invention includes:

[0034] like Figures 1 to 15 As shown, a parent-child screw injection molding device includes a base 100, a driving mechanism 200, a barrel 300 and a screw 400, the driving mechanism 200 is slidably connected to the base 100, the barrel 300 is fixedly connected to the barrel seat 110 of the base 100, the barrel seat 110 is slidably connected to the base 100, the barrel 300 includes a front barrel 310 and a rear barrel 320, the rear barrel 320 is provided with a feed port 321, the barrel seat 110 is equipped with a hopper 500 and the position of the hopper 500 Corresponding to the position of the feed port 321, one end of the screw 400 is inserted into the barrel 300, and its end is detachably connected to the mother screw head 410, and the other end is transmission-connected to the driving mechanism 200, and the mother screw head 410 is equipped with a sub-screw head 420, and the sub-screw head 420 cooperates with the pressurized inner cavity 340 in the front barrel 310, or a second-stage sub-screw head 430 is installed at the front end of the sub-screw head 420, and the second-stage sub-screw head 430 cooperates with the pressurized inner cavity 340 in the front barrel 310.

[0035] like Figures 4 to 7 As shown, the inner wall surface of the rear barrel 320 has a reflux groove 330, and the reflux groove 330 is in the shape of a groove, or can be as follows Fig.10 As shown, the inner wall surface of the front barrel 310 has a reflux groove 330, and the reflux groove 330 is groove-shaped. Of course, it is also possible that the inner wall surface of the front barrel 310 and the inner wall surface of the rear barrel 320 both have a reflux groove 330, and the reflux groove 330 is groove-shaped.

[0036] Of course, it can also be Figures 8-9 As shown, the inner wall surface of the rear barrel 320 has a reflux hole 331 and a reflux channel 332, and the reflux channel 332 is in a tunnel shape, or vice versa, the inner wall surface of the front barrel 310 has a reflux hole 331 and a reflux channel 332, and the reflux channel 332 is in a tunnel shape. Of course, it is also possible that the inner wall surface of the front barrel 310 and the inner wall surface of the rear barrel 320 both have a reflux hole 331 and a reflux channel 332, and the reflux channel 332 is in a tunnel shape.

[0037] Of course, it can also be Fig.12As shown, the inner wall surface of the front barrel 310 has a reflux groove 330, and the inner wall surface of the rear barrel 320 has a reflux hole 331 and a reflux channel 332, and the reflux groove 330 is groove-shaped, and the reflux channel 332 is tunnel-shaped; or vice versa, as shown in FIG. Fig.13 As shown, the inner wall surface of the front barrel 310 is provided with a reflux hole 331 and a reflux channel 332 thereof, and the inner wall of the rear barrel 320 is provided with a reflux groove 330 , and the reflux groove 330 is groove-shaped, and the reflux channel 332 is tunnel-shaped.

[0038] like Figures 6-7 As shown, the sub-screw head 420 is threadedly connected to the female screw head 410, the female screw head 410 is provided with a female check ring 411, and the outer wall surface of the front barrel 310 is provided with a check valve 311. Since the sub-check ring 421 is easily degraded when processing certain plastic raw materials, in this case, it is more beneficial to product quality to not set the sub-check ring 421 but set the check valve 311 on the outer wall surface of the front barrel 310.

[0039] like Figure 1 , 2 As shown, the driving mechanism 200 includes an injection cylinder 210, an oil motor 220, a cylinder seat 230 and a driving seat 240. The driving seat 240 is slidably connected to the base 100, the oil motor 220 is fixedly connected to the driving seat 240, the cylinder seat 230 is fixedly connected to the barrel seat 110 or is integrated with the barrel seat 110, the outer end of the piston rod of the injection cylinder 210 is fixedly connected to the driving seat 240, and the other end of the screw 400 is transmission-connected to the oil motor 220.

[0040] like Figure 4 , 5 As shown in , 8 and 9 , the sub-screw head 420 is threadedly connected to the female screw head 410 , the female screw head 410 is sleeved with a female check ring 411 , and the sub-screw head 420 is sleeved with a sub-check ring 421 .

[0041] like Fig.10 As shown, the sub-screw head 420 is threadedly connected to the female screw head 400, and a sub-check ring 421 is mounted on the sub-screw head 420. A secondary sub-screw head 430 is threadedly connected to the front end of the sub-screw head 420, and a secondary check ring 431 is mounted on the secondary sub-screw head 430. At this time, the female screw head 400 can also be mounted with a female check ring 411 to facilitate material recycling.

[0042] like Fig.11 As shown, the front end periphery of the sub-screw head 420 has a pushing screw rib 422 .

[0043] like Fig.14 As shown, the rear end of the front barrel 310 has an inner diameter enlarged section, which can also be as follows Fig.15As shown, the front end of the rear barrel 320 has an enlarged inner diameter section, and the enlarged inner diameter can naturally return the material, play the role of the reflux groove 330 or the reflux hole 331 and its reflux channel 332, and reduce processing. However, the use of the reflux groove 330 or the reflux hole 331 and its reflux channel 332 can save materials and have better effects.

[0044] like Figures 1-2 As shown, a movable cylinder 700 is installed between the drive seat 240 and the template of the mold 600, which is used to fix the drive seat 240 so that it cannot move relative to the template of the mold 600 when the injection molding device is working, and to push the drive seat 240 out when the injection molding device is not working, so as to facilitate cleaning of the injection molding device.

[0045] like Figure 2 As shown, when the present invention is in use, its driving seat 240 is fixedly connected to the outer end of the piston of the mobile oil cylinder 700, and the material is first added to the hopper 500, and then the oil motor 200 drives the screw 400 to rotate, and the plastic raw material enters the barrel 300 from the hopper 500. The screw 400 rotates to push the plastic forward for plasticization, and the plastic pushes the female check ring 411 and the sub-check ring 421 to the front end, and from the inside of the female check ring 411 along the feeding channel of the female screw head 410 to the front end of the sub-screw head 420 at the front of the screw 400, and at this time, the screw 400 is pushed. 00 oil motor 200 moves backward, and the corresponding raw materials are added according to the size of the product. When the addition is completed, during injection, the piston of the injection cylinder 210 moves forward, driving the drive seat 240 and the screw 400 to move forward as well. The female check ring 411 on the female screw head 410 and the sub-check ring 421 on the sub-screw head 420 slide to the rear end and close the feed channel on the female screw head 410. The plastic is injected into the mold 600 from the nozzle of the front barrel 310 under the push of the screw 400. At this time, the injection pressure of the mold cavity does not need to be too high. When the plastic is almost filled When the mold cavity needs to maintain pressure, the sub-screw head 420 enters the front barrel 310 and the rear end of the female check ring 411 moves to the channel opening of the reflux groove 330 or the opening of the reflux hole 331. The plastic bypasses the female check ring 411 from the reflux groove 330 or the reflux hole 331 and its reflux channel 332 to its rear end. The front end of the female screw head 410 loses pressure. At this time, the sub-screw head 420 and the front barrel 310 start to work. The end area of ​​the sub-screw head 420 can be made much smaller than the end area of ​​the female screw head 410 (depending on the actual needs of the end surface area). The volume can be made several times smaller, and the corresponding pressure can also be several times the pressure generated by the female screw head 410. The general cavity pressure is 250-300cm2 / kg), so the cavity pressure is high pressure or ultra-high pressure, more than one thousand kilograms per square centimeter (in traditional practice, expensive gas-assisted injection equipment can only reach a maximum of 700 kilograms per square centimeter). The injection molding machine computer controls the last injection and secondary holding pressure flexibly, and the processed plastic products can be shrink-free, high quality, high density, and high strength.

[0046] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A parent-child screw injection molding device, comprising a base (100), a driving mechanism (200), a barrel (300) and a screw (400), wherein the driving mechanism (200) is slidably connected to the base (100), the barrel (300) is fixedly connected to a barrel seat (110) of the base (100), the barrel seat (110) is slidably connected to the base (100), and the barrel (300) comprises a front barrel (310) and a rear barrel (320), the rear barrel (320) being provided with a feed port (321), the barrel seat (110) being provided with a hopper (500) and the position of the hopper (500) corresponding to the position of the feed port (321), one end of the screw (400) being inserted into the barrel (300), and the end of the screw (400) being detachably connected with a female screw head (410), and the other end being transmission-connected with a driving mechanism (200), characterized in that: a. The female screw head (410) is provided with a sub-screw head (420); The sub-screw head (420) cooperates with the pressurized inner cavity (340) in the front barrel (310), or a second-stage sub-screw head (430) is installed at the front end of the sub-screw head (420), and the second-stage sub-screw head (430) cooperates with the pressurized inner cavity (340) in the front barrel (310); b. The inner wall surface of the front barrel (310) or the inner wall surface of the rear barrel (320) has a channel opening of a reflux groove (330), and the reflux groove (330) is in the shape of a groove; or, the inner wall surface of the front barrel (310) or the inner wall surface of the rear barrel (320) has an opening of a reflux hole (331) and a reflux channel (332), and the reflux channel (332) is in the shape of a tunnel; or, the rear end of the front barrel (310) has an inner diameter enlarged section or the front end of the rear barrel (320) has an inner diameter enlarged section; c. The sub-screw head (420) is threadedly connected to the female screw head (410), and the female screw head (410) is provided with a female check ring (411); The sub-screw head (420) is provided with a sub-check ring (421) or the outer wall surface of the front barrel (310) is provided with a check valve (311); d. The end area of ​​the sub-screw head (420) is several times smaller than the end area of ​​the mother screw head (410); e. When a second-stage sub-screw head (430) is installed at the front end of the sub-screw head (420), a second-stage check ring (431) is mounted on the second-stage sub-screw head (430).

2. The parent-child screw injection molding device according to claim 1, characterized in that: The driving mechanism (200) comprises an injection cylinder (210), an oil motor (220), a cylinder seat (230) and a driving seat (240); the driving seat (240) is slidably connected to the base (100); the oil motor (220) is fixedly connected to the driving seat (240); the cylinder seat (230) is fixedly connected to the barrel seat (110) or is integrated with the barrel seat (110); the outer end of the piston rod of the injection cylinder (210) is fixedly connected to the driving seat (240); and the other end of the screw rod (400) is drivingly connected to the oil motor (220).

3. The parent-child screw injection molding device according to claim 1, characterized in that: The front end periphery of the sub-screw head (420) is provided with a pushing screw ridge (422).

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