Injection molding assembly and injection molding machine

Abstract

The utility model provides a kind of injection molding assembly and injection molding machine, it is related to injection molding field.The injection molding assembly includes cylinder barrel and screw, cylinder barrel is arranged along first direction, and inside is formed with accommodating cavity;The side wall of cylinder barrel is equipped with feed inlet, the front end of cylinder barrel is equipped with discharge port, feed inlet and discharge port are communicated with accommodating cavity respectively;The front end of screw screw is inserted into accommodating cavity;The tail end of screw is located outside accommodating cavity, to be connected with driving device;There is gap between the front end of screw and the inner wall of accommodating cavity.The inner cavity of accommodating cavity is conical along first direction, and along the direction away from the tail of cylinder barrel, the cross-sectional area of accommodating cavity gradually increases.The utility model is designed as the inner cavity of accommodating cavity is conical along first direction, avoids the direct rigid contact of screw with the inner wall of cylinder barrel in high-speed rotation and axial movement process, reduces the incidence of friction and abrasion and metal debris pollution to molten material, beneficial to improve injection molding quality.

Description

Technical Field

[0001] This utility model belongs to the field of injection molding technology, and in particular relates to an injection molding component and an injection molding machine. Background Technology

[0002] In injection molding equipment, the barrel and screw are the core components that achieve material plasticization and conveying. During operation, the screw rotates and reciprocates axially within the barrel under the drive of the drive unit, pushing the material through the thread and coordinating with heating to melt and plasticize the material, which is then injected into the mold cavity through the outlet.

[0003] In existing technologies, the inner wall of the barrel is often designed as a cylindrical structure adapted to the screw, and the two must maintain a high degree of fit to ensure material conveying efficiency. However, during long-term high-frequency operation, the screw is prone to axial misalignment or circumferential twisting due to factors such as fluctuations in driving torque and uneven resistance of the material. This leads to a sudden increase in local contact stress between the outer wall of the screw and the inner wall of the barrel, resulting in continuous frictional wear. This wear problem not only causes the fit clearance between the barrel and the screw to gradually increase, leading to problems such as material backflow and uneven plasticization, reducing injection molding accuracy and product quality; it also generates debris due to metal surface wear, contaminating the molten material, posing a serious quality hazard, especially in high-precision injection molding fields (such as medical and electronic components). Utility Model Content

[0004] In view of this, the present invention provides an injection molding component and an injection molding machine, which aim to reduce or avoid wear between the screw and the inner wall of the barrel.

[0005] The technical solution of this utility model is implemented as follows:

[0006] This utility model provides an injection molding assembly, which includes a barrel arranged along a first direction and having a receiving cavity inside; a feed inlet is provided on the side wall of the barrel, and a discharge outlet is provided at the front end of the barrel, the feed inlet and the discharge outlet being respectively connected to the receiving cavity; and a screw, the front end of the screw extending into the receiving cavity; the tail end of the screw located outside the receiving cavity for connection to a driving device; a gap between the front end of the screw and the inner wall of the receiving cavity; wherein, the inner cavity of the receiving cavity is conical along the first direction, and the cross-sectional area of ​​the receiving cavity gradually increases along the direction away from the tail end of the barrel.

[0007] In one embodiment, the outer peripheral wall of the screw is provided with a helically extending thread, the pitch of which gradually decreases in the direction away from the tail of the barrel.

[0008] In one embodiment, a wear-resistant sleeve is further included around the screw. The barrel includes: a barrel body with the receiving cavity formed inside; an end cap that covers the tail end of the barrel body, wherein the screw extends into the barrel body through the end cap; a first notch is formed on the inner sidewall of the end cap, and an annular second notch is formed on the inner sidewall of the barrel body. The first notch and the second notch are joined to form a groove, and the wear-resistant sleeve is disposed in the groove; the inner wall surface of the wear-resistant sleeve is conical to fit against the outer wall surface of the screw.

[0009] In one embodiment, a first sealing element is further included, wherein an annular first receiving groove is formed on the outer side wall of the wear-resistant sleeve, and the first sealing element is installed in the first receiving groove to seal the gap between the outer side wall of the wear-resistant sleeve and the first notch or the gap between the outer side wall of the wear-resistant sleeve and the second notch.

[0010] In one embodiment, a second sealing element is further included, and an annular third notch is formed on the inner sidewall of the end cap; in a direction perpendicular to the first direction, the annular diameter of the third notch is smaller than the annular diameter of the first notch; the second sealing element is disposed within the third notch.

[0011] In one embodiment, a third seal is also included; the inner wall of the wear-resistant sleeve is provided with an annular second receiving groove, and the third seal is disposed in the second receiving groove.

[0012] In one embodiment, the second receiving groove is disposed near the tail end of the screw.

[0013] In one embodiment, a fourth sealing element is further included; the fourth sealing element is sandwiched between the end cap and the end face of the cylinder body.

[0014] In one embodiment, a heating system is also included, wherein the pipes of the heating system are arranged around the outer wall of the cylindrical body.

[0015] This utility model also provides an injection molding machine, the injection molding assembly including the barrel and the screw; a feeding device connected to the feed port of the barrel for feeding injection molding raw materials into the barrel; a driving device including a hydraulic cylinder and a servo motor, the servo motor being mounted on the screw seat; the hydraulic cylinder for driving the screw forward and backward, the servo motor for driving the screw to rotate; and an injection mold connected to the discharge port of the barrel for receiving molten raw materials injected through the discharge port of the barrel and forming injection molded products.

[0016] The injection molding assembly provided by this utility model includes a barrel and a screw. The barrel is arranged along a first direction and has a receiving cavity inside. A feed inlet is provided on the side wall of the barrel, and a discharge outlet is provided at the front end of the barrel. The feed inlet and discharge outlet are respectively connected to the receiving cavity. The front end of the screw extends into the receiving cavity; the tail end of the screw is located outside the receiving cavity for connection to a drive device. There is a gap between the front end of the screw and the inner wall of the receiving cavity. The inner cavity of the receiving cavity is conical along the first direction, and its cross-sectional area gradually increases along the direction away from the tail end of the barrel. This utility model avoids direct rigid contact between the screw and the inner wall of the barrel during high-speed rotation and axial movement by designing the receiving cavity as a conical structure with a gradually increasing cross-sectional area along the first direction and by leaving a gap between the front end of the screw and the inner wall of the receiving cavity. When the screw experiences axial misalignment or circumferential torsion due to fluctuations in driving torque or uneven material resistance, the conical inner wall of the receiving cavity provides a certain buffer space for the screw, reducing local contact stress and thus lowering the incidence of friction and wear, extending the service life of the injection molded components. It also prevents metal debris generated by wear from contaminating the molten material, which is beneficial to improving the quality stability of injection molded products. It is especially suitable for high-precision injection molding fields such as medical and electronic components where high material purity is required. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 A cross-sectional view of the injection molding assembly provided by this utility model;

[0019] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0020] Figure 3 This is a schematic diagram of the injection molding machine provided by this utility model.

[0021] Explanation of reference numerals in the attached figures:

[0022] 100. Injection molding assembly; 1. Barrel; 10. Receiving cavity; 11. Inlet; 12. Outlet; 13. Barrel body; 131. First notch; 14. End cap; 141. Second notch; 142. Third notch; 2. Screw; 21. Thread; 3. Wear-resistant sleeve; 4. First seal; 5. Second seal; 6. Third seal; 7. Fourth seal; 200. Feeding device; 300. Drive device; 301. Hydraulic cylinder; 302. Servo motor; 400. Injection mold. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0024] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0025] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. "Multiple" refers to two or more. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0026] In injection molding equipment, the barrel and screw are the core components that achieve material plasticization and conveying. During operation, the screw rotates and reciprocates axially within the barrel under the drive of the drive unit, pushing the material through the thread and coordinating with heating to melt and plasticize the material, which is then injected into the mold cavity through the outlet.

[0027] In existing technologies, the inner wall of the barrel is often designed as a cylindrical structure adapted to the screw, and the two must maintain a high degree of fit to ensure material conveying efficiency. However, during long-term high-frequency operation, the screw is prone to axial misalignment or circumferential twisting due to factors such as fluctuations in driving torque and uneven resistance of the material. This leads to a sudden increase in local contact stress between the outer wall of the screw and the inner wall of the barrel, resulting in continuous frictional wear. This wear problem not only causes the fit clearance between the barrel and the screw to gradually increase, leading to problems such as material backflow and uneven plasticization, reducing injection molding accuracy and product quality; it also generates debris due to metal surface wear, contaminating the molten material, posing a serious quality hazard, especially in high-precision injection molding fields (such as medical and electronic components).

[0028] In view of this, the present invention provides an injection molding component designed to reduce or avoid wear between the screw and the inner wall of the barrel.

[0029] Please see Figure 1 The injection molding assembly 100 includes a barrel 1 and a screw 2. The barrel 1 is arranged along a first direction and has a receiving cavity 10 inside. The side wall of the barrel 1 has an inlet 11 and the front end has an outlet 12, which are respectively connected to the receiving cavity 10. The first direction is also the front-rear direction of the barrel 1, which is represented by the dashed line a in the figure.

[0030] The front end of the screw 2 extends into the receiving cavity 10, and the tail end is located outside the receiving cavity 10 to be connected to the drive device 300. Furthermore, there is a gap between the front end of the screw 2 and the inner wall of the receiving cavity 10. This design ensures that when the screw 2 rotates at high speed, its front end will not directly and rigidly contact the inner wall of the barrel 1, thereby effectively reducing the risk of local friction and wear caused by the deflection or twisting of the screw 2.

[0031] Furthermore, the inner cavity of the receiving cavity 10 is conical along the first direction, and the cross-sectional area of ​​the receiving cavity 10 gradually increases along the direction away from the tail of the barrel 1. This conical structure, combined with the front end clearance design of the screw 2, not only provides a reasonable spatial gradient for the material during the plasticizing process, facilitating the gradual compression and melting of the material, but also reduces the probability of contact between the screw 2 and the inner wall of the barrel 1 through the guiding effect of the conical inner wall when the screw 2 is slightly deflected due to force, further alleviating the wear problem.

[0032] To create a cylinder 1 with an internal conical receiving cavity 10, a cylindrical material can be selected first, and a conical hole can be drilled inside it to form a pre-formed cylinder with an internal conical hole. Next, a sheet material is selected, and the larger end of the conical hole in the pre-formed cylinder is sealed by welding. This sheet material has the aforementioned discharge port 12. Finally, a cap 14 is placed on the smaller end of the conical hole in the pre-formed cylinder.

[0033] In summary, the injection molding assembly 100 provided in this embodiment includes a barrel 1 and a screw 2. The barrel 1 is arranged along a first direction and has a receiving cavity 10 inside. A feed inlet 11 is provided on the side wall of the barrel 1, and a discharge outlet 12 is provided at the front end of the barrel 1. The feed inlet 11 and the discharge outlet 12 are respectively connected to the receiving cavity 10. The front end of the screw 2 extends into the receiving cavity 10. The tail end of the screw 2 is located outside the receiving cavity 10 to connect with the driving device 300. There is a gap between the front end of the screw 2 and the inner wall of the receiving cavity 10. The inner cavity of the receiving cavity 10 is conical along the first direction, and its cross-sectional area gradually increases along the direction away from the tail end of the barrel 1. This embodiment of the invention avoids direct rigid contact between the screw 2 and the inner wall of the barrel 1 during high-speed rotation and axial movement by designing the receiving cavity 10 as a conical structure with a gradually increasing cross-sectional area along the first direction and reserving a gap between the front end of the screw 2 and the inner wall of the receiving cavity 10. When the screw 2 experiences axial misalignment or circumferential twisting due to fluctuations in driving torque or uneven material resistance, the inner wall of the conical receiving cavity 10 can provide a certain buffer space for the screw 2, reducing local contact stress, thereby reducing the incidence of friction and wear, extending the service life of the injection molding assembly 100, and also preventing metal debris generated by wear from contaminating the molten material. This is beneficial to improving the quality stability of injection molded products, and is especially suitable for high-precision injection molding fields such as medical and electronic components where high material purity is required.

[0034] In some embodiments, please continue reading Figure 1 In order to adapt to the conical receiving cavity 10 of the barrel 1 and form a progressive compression, the thread 21 of the screw 2 was optimized. Specifically, the outer peripheral wall of the screw 2 is provided with a helical thread 21, and the pitch of the thread 21 gradually decreases in the direction away from the tail of the barrel 1.

[0035] On the one hand, it enables progressive compression of the material. As the material is conveyed from the tail end of the barrel 1 to the front end, the pitch gradually decreases, causing the space between the threads 21 to gradually shrink, creating a continuously increasing compressive force on the material. This progressive compression can prevent the material from overheating or degrading due to excessive instantaneous force, while gradually expelling air and volatiles contained in the material, reducing defects such as bubbles and shrinkage cavities in injection molded products, and improving the density of the material after plasticization.

[0036] On the other hand, it forms a synergistic fit with the conical receiving cavity 10. Since the cross-sectional area of ​​the receiving cavity 10 gradually increases away from the tail of the barrel 1, while the pitch gradually decreases simultaneously, the dimensional changes of the two are complementary: the compressive force generated by the decrease in pitch can counteract the material loosening that may result from the increase in the cross-sectional area of ​​the receiving cavity 10, ensuring that the material maintains a suitable filling degree and pressure during conveying, avoiding conveying interruptions or accumulation and congestion. Simultaneously, this fit allows for more uniform contact between the material and the inner wall of the barrel 1 when the screw 2 rotates and pushes, reducing wear caused by localized pressure concentration. Especially with the conical structure of the barrel 1, it can further alleviate localized friction when the screw 2 is misaligned or twisted, extending the service life of the component.

[0037] In some embodiments, please refer to Figure 1 and Figure 2 To reduce the direct wear on the inner wall of the barrel 1 caused by the screw 2's skewness or twisting, and to extend the service life of the barrel 1, the injection molding assembly 100 also includes a wear-resistant sleeve 3 fitted around the screw 2. Specifically, the barrel 1 includes a barrel body 13 and an end cap 14. The barrel body 13 has an internal cavity 10. The end cap 14 covers the tail end of the barrel body 13, through which the screw 2 extends into the barrel body 13. The inner wall of the end cap 14 has a first notch 131, and the inner wall of the barrel body 13 has an annular second notch 141. The first and second notches 141 are joined to form a groove, in which the wear-resistant sleeve 3 is disposed. The inner wall surface of the wear-resistant sleeve 3 is conical to fit against the outer wall surface of the screw 2.

[0038] The wear-resistant sleeve 3 can be made of copper. Its function is as follows: The wear-resistant sleeve 3 is set on the periphery of the screw 2 and is positioned and installed through the groove formed by the splicing of the end cap 14 and the barrel body 13. At the same time, the wear-resistant sleeve 3 adopts a conical inner wall design that fits against the outer wall of the screw 2, so that the wear-resistant sleeve 3 can act as an intermediate contact part to isolate the screw 2 from the inner wall of the barrel 1. This effectively concentrates the wear caused by the skew or twisting of the screw 2 onto the wear-resistant sleeve 3, thereby avoiding direct wear on the inner wall of the barrel 1 and extending the service life of the barrel 1. At the same time, the conical structure adapts to the shape changes of the screw 2, ensuring the stability of the fit, and the groove installation method ensures that the position of the wear-resistant sleeve 3 is fixed, thus improving the overall durability and maintenance convenience of the injection molding assembly 100.

[0039] In some embodiments, please continue reading Figure 1 and Figure 2To prevent molten material in the receiving cavity 10 from leaking through the gap between the outer wall of the wear-resistant sleeve 3 and the first notch 131 or the second notch 141, and to prevent external dust and impurities from entering the receiving cavity 10 and contaminating the material through this gap, the injection molding assembly 100 also includes a first seal 4. Specifically, the outer wall of the wear-resistant sleeve 3 forms an annular first receiving groove, and the first seal 4 is installed in the first receiving groove to seal the gap between the outer wall of the wear-resistant sleeve 3 and the first notch 131 or the gap between the outer wall of the wear-resistant sleeve 3 and the second notch 141.

[0040] The first sealing element 4 can be made of high-temperature resistant plastic. Its sealing principle is as follows: the first sealing element 4 effectively seals the fitting gap between the wear-resistant sleeve 3 and the first notch 131 and the second notch 141. On the one hand, it can prevent the molten material in the receiving cavity 10 from leaking outward along the gap, ensuring the pressure stability of the material during the conveying process, reducing material waste and avoiding equipment contamination caused by leakage. On the other hand, it can block dust, debris and other impurities in the external environment from entering the receiving cavity 10 through the gap, avoiding contamination of the molten material and ensuring the purity and quality of the injection molded product. At the same time, the annular first receiving groove reliably limits the first sealing element 4, preventing it from shifting or falling off due to vibration and friction during equipment operation, ensuring the long-term stability of the sealing effect.

[0041] In some embodiments, please continue reading Figure 1 and Figure 2 To further enhance the sealing layer and prevent material leakage from the outer periphery of the screw 2 towards the outside of the end cap 14 or external impurities from entering the receiving cavity 10 along this path, forming multiple sealing protections to improve overall sealing reliability, a second sealing element 5 is added. Furthermore, an annular third notch 142 is formed on the inner wall of the end cap 14; perpendicular to the first direction, the annular diameter of the third notch 142 is smaller than the annular diameter of the first notch 131; the second sealing element 5 is disposed within the third notch 142.

[0042] The second seal 5 can also be made of high-temperature resistant plastic. Its sealing principle is as follows: the third notch 142 forms a radial limit on the second seal 5, so that under its own elastic force or assembly pre-tightening force, the inner wall of the second seal 5 is tightly fitted with the outer peripheral wall of the screw 2, forming a line seal or surface seal along the radial direction of the screw 2. Since the annular diameter of the third notch 142 is smaller than that of the first notch 131, the installation position of the second seal 5 is closer to the axis of the screw 2, which can directly block the material or impurities flowing along the outer peripheral surface of the screw 2. When the material breaks through the protection of the first seal 4 and penetrates to the outside of the end cap 14, the second seal 5 can cut off the leakage path through close contact with the screw 2; at the same time, if external impurities attempt to invade along the outer periphery of the screw 2, they will also be blocked by the radial sealing structure of the second seal 5.

[0043] In some embodiments, please continue reading Figure 1 and Figure 2 To seal the fit gap between the inner wall of the wear-resistant sleeve 3 and the outer peripheral wall of the screw 2, and to prevent embrittlement, a third sealing element 6 is added. Furthermore, the inner wall of the wear-resistant sleeve 3 is provided with an annular second receiving groove, and the third sealing element 6 is disposed within the second receiving groove.

[0044] The third sealing element 6 can also be made of high-temperature resistant plastic. Its sealing principle is as follows: utilizing the elastic deformation capability of the high-temperature resistant plastic material itself, after assembly, under the limiting effect of the second receiving groove, the inner edge of the third sealing element 6 will form a tight fit with the outer peripheral wall of the screw 2, thereby forming a continuous elastic sealing surface at the fitting gap between the wear-resistant sleeve 3 and the screw 2. When the screw 2 rotates or deflects slightly, the high-temperature resistant plastic part can adapt to the movement of the screw 2, always maintaining the contact pressure with the outer peripheral wall of the screw 2, effectively preventing the molten material in the receiving cavity 10 from flowing back along the gap; at the same time, its elastic recovery force can compensate for the change in the sealing surface gap caused by long-term wear, maintaining a stable sealing effect. In addition, the selected high-temperature resistant plastic material can withstand the high-temperature environment (usually above 200°C) in the barrel 1, avoiding loss of elasticity due to high-temperature aging, ensuring that it can still maintain good sealing performance under the high-temperature working conditions of material plasticization, further improving the overall sealing system of the component.

[0045] In some embodiments, please continue reading Figure 1 and Figure 2 In order to form an effective seal in the initial stage when the material enters the gap between the wear-resistant sleeve 3 and the screw 2, and to block the leakage path of the material towards the tail end of the screw 2 in advance, and to form a progressive protection along the axial direction with other sealing structures, thereby enhancing the comprehensiveness and reliability of the seal, the second receiving groove is set close to the tail end of the screw 2.

[0046] In some embodiments, please continue reading Figure 1 and Figure 2 In order to seal the gap between the mating end face of the end cap 14 and the cylinder body 13, prevent the molten material in the receiving cavity 10 from leaking outward from the gap, and prevent dust, water vapor and other impurities in the external environment from entering the receiving cavity 10 through the gap and contaminating the material, a fourth sealing element 7 is added; and a fourth sealing element 7 is sandwiched between the end face of the end cap 14 and the cylinder body 13.

[0047] In some embodiments, please continue reading Figure 1 and Figure 2 In order to melt the plastic granules in the barrel, a heating system was added, and the pipes of the heating system were arranged around the outer wall of the barrel body 13.

[0048] This utility model embodiment also provides an injection molding machine.

[0049] Please see Figure 3 The injection molding machine includes a feeding device 200, a drive device 300, an injection mold 400, and the aforementioned injection molding assembly 100. The injection molding assembly 100 includes a barrel 1 and a screw 2; the feeding device 200 is connected to the feed port 11 of the barrel 1 and is used to feed the injection molding material into the barrel 1; the drive device 300 includes a hydraulic cylinder 301 and a servo motor 302, the servo motor 302 being mounted on the screw seat; the hydraulic cylinder 301 is used to drive the screw 2 forward and backward, and the servo motor 302 is used to drive the screw 2 to rotate; the injection mold 400 is connected to the discharge port 12 of the barrel 1 and is used to receive the molten material injected through the discharge port 12 of the barrel 1 and form the injection molded product.

[0050] The injection molding principle is as follows: The feeding device 200 conveys the injection molding raw material through the feed port 11 of the barrel 1 into the receiving cavity 10. The servo motor 302 drives the screw 2 to rotate within the receiving cavity 10. Under the pushing action of the screw 2 and the heating system, the raw material gradually melts and plasticizes. As the screw 2 continues to rotate, the molten material is continuously conveyed forward and accumulates at the front end of the barrel 1. When the material pressure reaches a preset value, the hydraulic cylinder 301 drives the screw 2 to move forward, injecting the molten material at high speed into the cavity of the injection mold 400 through the discharge port 12. After the material cools and solidifies in the mold, the mold opens and the product is removed, completing one injection molding cycle. During this process, the conical receiving cavity 10 of the injection molding component 100, the front end clearance design of the screw 2, and the setting of the wear-resistant sleeve 3 and multiple seals ensure uniform plasticization and stable conveying of the material, effectively reducing wear and contamination, and improving the operational reliability and product quality of the injection molding machine.

[0051] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. An injection-molded component, characterized in that, include: A material cylinder is arranged along a first direction and has an internal receiving cavity; the side wall of the material cylinder has a feed inlet and the front end of the material cylinder has a discharge outlet, and the feed inlet and the discharge outlet are respectively connected to the receiving cavity; A screw, the front end of which extends into the receiving cavity; the tail end of which is located outside the receiving cavity for connection with a drive device; and a gap between the front end of the screw and the inner wall of the receiving cavity. The inner cavity of the receiving cavity is conical along the first direction, and the cross-sectional area of ​​the receiving cavity gradually increases along the direction away from the tail of the barrel.

2. The injection-molded assembly according to claim 1, characterized in that, The outer peripheral wall of the screw is provided with a helical thread, and the pitch of the thread gradually decreases in the direction away from the tail of the barrel.

3. The injection-molded assembly according to claim 1 or 2, characterized in that, It also includes a wear-resistant sleeve fitted around the screw, and the barrel includes: The cylindrical body has the aforementioned receiving cavity formed inside; End cap, which fits onto the tail end of the cylinder body. The screw extends into the cylinder body through the end cap; a first notch is formed on the inner sidewall of the end cap, and a second annular notch is formed on the inner sidewall of the cylinder body. The first notch and the second notch are joined together to form a groove, and the wear-resistant sleeve is disposed in the groove; the inner wall surface of the wear-resistant sleeve is conical to fit against the outer wall surface of the screw.

4. The injection-molded assembly according to claim 3, characterized in that, It also includes a first sealing element, wherein the outer side wall of the wear-resistant sleeve is formed with an annular first receiving groove, and the first sealing element is installed in the first receiving groove to seal the gap between the outer side wall of the wear-resistant sleeve and the first notch or the gap between the outer side wall of the wear-resistant sleeve and the second notch.

5. The injection-molded assembly according to claim 3, characterized in that, It also includes a second seal, and the inner sidewall of the end cap is further formed with an annular third notch; in the direction perpendicular to the first direction, the annular diameter of the third notch is smaller than the annular diameter of the first notch; the second seal is disposed in the third notch.

6. The injection-molded assembly according to claim 3, characterized in that, It also includes a third seal; the inner wall of the wear-resistant sleeve is provided with an annular second receiving groove, and the third seal is disposed in the second receiving groove.

7. The injection-molded assembly according to claim 6, characterized in that, The second receiving groove is located near the tail end of the screw.

8. The injection-molded assembly according to claim 3, characterized in that, It also includes a fourth sealing element; the fourth sealing element is sandwiched between the end cap and the end face of the cylinder body.

9. The injection-molded assembly according to claim 3, characterized in that, It also includes a heating system, the pipes of which are arranged around the outer wall of the cylinder body.

10. An injection molding machine, characterized in that, include: The injection molding assembly according to any one of claims 1 to 9, the injection molding assembly comprising the barrel and the screw; A feeding device, connected to the feed inlet of the barrel, is used to feed injection molding raw materials into the barrel; The driving device includes a hydraulic cylinder and a servo motor, the servo motor being mounted on a screw seat; the hydraulic cylinder is used to drive the screw forward and backward, and the servo motor is used to drive the screw to rotate. An injection mold is connected to the outlet of the barrel and is used to receive molten raw materials injected through the outlet of the barrel and form injection molded products.

Images