A mold with a new thread unthreading mechanism

Abstract

The utility model discloses a mould with novel thread unthreading mechanism, including front mould subassembly, rear mould subassembly and thread unthreading mechanism, and the front mould subassembly includes front mould plate, and the rear mould subassembly includes rear mould push plate, support plate group and thimble plate group, and the thread unthreading mechanism includes recurved line bar, and the recurved line bar is screwing and is equipped with recurved line mother, and one side of recurved line mother is provided with thread insert, and the thread insert is connected through gear assembly between recurved line mother, and the outside of thread insert is screwing and is equipped with thread sleeve, and the head of thread insert passes through rear mould push plate and extends to the cavity, and the thimble plate group can drive the relative movement of recurved line bar to recurved line mother, and the linear motion of recurved line bar is converted into the rotary motion of recurved line mother, and recurved line mother drives thread insert to rotate through gear assembly again, and thread insert can also move to the rear mould direction under the action of thread sleeve, and the product is separated from the reverse buckling, and does not need additional power source.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, specifically to a mold with a novel unscrew mechanism. Background Technology

[0002] The thread-removing mechanism (also known as the unscrew mechanism) in injection molds is a special device used to remove threaded plastic parts (such as threaded sleeves, bottle caps, etc.) from the mold. Its characteristic is that the thread engagement is released by rotation or separation.

[0003] Existing conventional thread unwinding mechanisms typically use hydraulic cylinders or servo motors to achieve relative rotation or separation between the threaded core / ring and the plastic part, thereby releasing the thread engagement and completing demolding. However, such thread unwinding mechanisms usually require an additional integrated power source, especially in two-color molds, which will occupy a large amount of space inside or around the mold, directly leading to a significant increase in the overall length, width, or height of the mold. This not only places higher demands on the tonnage and installation space of the injection molding machine (requiring adaptation to larger mold specifications), but also increases the mold manufacturing cost and the difficulty of transportation and maintenance. At the same time, the reduced compactness may also indirectly affect the stability of mold operation. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of the existing technology and provide a mold with a novel thread unscrew mechanism. The ejector plate assembly drives the rewinding rod to move relative to the rewinding nut, converting the linear motion of the rewinding rod into the rotational motion of the rewinding nut. The rewinding nut then drives the thread insert to rotate through the gear assembly. Under the action of the thread sleeve, the thread insert can also move towards the rear mold while rotating, disengaging from the product undercut without the need for an additional power source.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A mold with a novel thread-unscrew mechanism includes a front mold assembly, a rear mold assembly, and a thread-unscrew mechanism disposed within the rear mold assembly. The front mold assembly includes a front template, and the rear mold assembly includes a rear mold push plate, a support plate assembly, and an ejector plate assembly arranged sequentially from front to back. After the mold is closed, a cavity is formed between the front template and the rear mold push plate. The thread unscrew mechanism includes a reciprocating rod that can move synchronously with the ejector plate assembly. A reciprocating nut is screwed onto the reciprocating rod. The reciprocating nut is located within the support plate assembly. A threaded insert that can rotate in conjunction with the reciprocating nut is provided on one side of the reciprocating nut. The threaded insert and the reciprocating nut are connected by a gear assembly. A threaded sleeve is screwed onto the outer side of the threaded insert. The head of the threaded insert extends through the rear mold push plate into the cavity.

[0006] Optionally, the root of the reciprocating rod is fixedly connected to the ejector plate assembly, the reciprocating nut is rotatably installed in the support plate assembly, and the threaded sleeve is fixedly installed in the support plate assembly.

[0007] Optionally, the gear assembly includes a driving gear and a driven gear that mesh with each other. The driving gear is fixedly sleeved on the outside of the riveting nut, and the driven gear is fixedly sleeved on the outside of the threaded insert.

[0008] Optionally, the ejector plate assembly includes an overlapping ejector plate and an ejector base plate, and a positioning sleeve is fixedly sleeved at the root of the reciprocating rod, the positioning sleeve being disposed between the ejector plate and the ejector base plate.

[0009] Optionally, the ejector pin base plate is further provided with an adjustment block for adjusting the rotational position of the reciprocating rod, and the adjustment block is engaged with the positioning sleeve.

[0010] Optionally, the support plate assembly includes a first support plate, a second support plate, and a third support plate arranged sequentially from front to back. The threaded sleeve is fixedly installed in the second support plate, the gear assembly is located in the first support plate, and the root of the threaded insert is located in the third support plate.

[0011] Optionally, the front mold plate is provided with a hot runner plate, a front mold plate and a heat insulation plate in sequence from back to front on the side opposite to the rear mold push plate, and the ejector plate assembly is provided with a rear mold bottom plate on the side opposite to the rear mold push plate.

[0012] Optionally, a mold foot is provided between the support plate assembly and the rear mold base plate, and the ejector plate assembly is located inside the mold foot.

[0013] Optionally, two sets of the thread unwinding mechanism are provided, and the two sets of the thread unwinding mechanism are symmetrically distributed in the rear mold assembly.

[0014] Optionally, each of the aforementioned unscrewing mechanisms is provided with multiple thread inserts, which are arranged in a circumferential array around the axis of the reciprocating rod.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: In this invention, after the mold is opened, the ejector plate assembly drives the riveting rod to push out towards the front mold. The riveting nut rotates under the action of the riveting rod and drives the threaded insert to rotate together through the gear assembly. While the threaded insert rotates, it moves towards the rear mold through the threaded sleeve and disengages from the product undercut. The thread-unscrewing mechanism adopted by this mold can make its arrangement compact, reduce the mold size, and achieve the disengagement of products with threads without the need for an additional power source. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a mold with a novel unscrew mechanism in an embodiment of this utility model; Figure 2 This is a schematic diagram of the unscrew mechanism in an embodiment of this utility model; The components are as follows: 1. Heat insulation plate; 2. Front mold panel; 3. Hot runner plate; 4. Front mold plate; 5. Rear mold push plate; 6. Support plate assembly; 7. Mold foot; 8. Ejector plate; 9. Ejector base plate; 10. Rear mold base plate; 11. Threaded insert; 12. Threaded sleeve; 13. Gear assembly; 131. Drive gear; 132. Driven gear; 14. Rifling screw nut; 15. Rifling rod; 16. Positioning sleeve; 17. Adjusting block. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. These drawings are simplified schematic diagrams, which are only used to illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0018] Example 1, as Figure 1 and Figure 2 As shown, a mold with a novel thread-unscrew mechanism includes a front mold assembly, a rear mold assembly, and a thread-unscrew mechanism. After the mold is closed, a cavity for injection molding products is formed between the front mold assembly and the rear mold assembly. The thread-unscrew mechanism is located inside the rear mold assembly, and after the mold is opened, the threaded product can be unscrewed under the action of the injection molding machine ejector rod. No additional power source such as hydraulic cylinders or servo motors is required. It is particularly suitable for two-color molds where the product has threads but hydraulic cylinders or servo motors cannot be installed.

[0019] The front mold assembly includes a front template 4, a hot runner plate 3, a front mold panel 2, and a heat insulation plate 1 arranged sequentially from back to front. The front template 4 is used to fix the front mold cavity, and integrates the mating holes of guide pillars and guide sleeves to ensure accurate positioning of the mold when it is closed. It also provides installation reference and structural support for components such as the hot runner plate 3 and the front mold panel 2.

[0020] The function of the hot runner plate 3 is to distribute and control the material flow. It has a main runner and a branch runner. The branch runner corresponds to each cavity of the multi-cavity mold and can maintain the plastic melt in the runner at a constant temperature to prevent the material flow from solidifying and achieve continuous injection. At the same time, it evenly distributes the melt delivered by the injection molding machine nozzle to each hot nozzle and finally enters the cavity.

[0021] The function of the front mold panel 2 is to fix the entire front mold system to the fixed mold side of the injection molding machine with bolts. At the same time, it provides mounting holes for the positioning ring (the positioning part that connects the mold and the injection molding machine nozzle), ensuring that the injection molding machine nozzle and the main runner of the mold are accurately aligned. It can also protect the precision components inside the front mold, such as the hot runner plate 3 and the front mold plate 4, from external impact or contamination.

[0022] The heat insulation plate 1 is installed on the rear side of the front mold panel 2. Its function is to block the high temperature of the hot runner plate 3 from being transmitted to the injection molding machine. On the one hand, it prevents the injection molding machine from being damaged by high temperature, and on the other hand, it reduces the heat loss of the hot runner system and reduces the energy consumption of temperature control.

[0023] The rear mold assembly includes, from front to back, a rear mold push plate 5, a support plate assembly 6, mold feet 7, an ejector plate assembly, and a rear mold base plate 10. The rear mold push plate 5 is installed against the front end of the rear mold core. Its function is to participate in the demolding of the plastic part. The rear mold push plate 5 can make a linear ejection movement along the core axis to push the plastic part out of the core as a whole, avoiding deformation of the plastic part caused by single-point ejection of the ejector pin. At the same time, the push plate cooperates with the guide pillars and guide sleeves to guide and position the part during the ejection process, ensuring smooth movement.

[0024] The support plate assembly 6 is located between the rear mold push plate 5 and the mold foot 7. It includes a first support plate, a second support plate, and a third support plate arranged sequentially from front to back. Its main function is to fix the rear mold core and withstand the huge pressure of the melt on the core during injection molding, preventing the core from shifting, deforming, or sinking due to force, and ensuring the dimensional accuracy of the molded plastic part. In addition, the support plate assembly 6 is machined with clearance holes to provide space for the movement of the ejector element of the unscrew mechanism, and at the same time to provide an installation reference for the mold foot 7, ensuring the rigidity and stability of the rear mold structure.

[0025] The mold foot 7, also called a pad or square iron, consists of two symmetrically installed block-shaped structural components between the third support plate and the rear mold base plate 10. It forms a movement space for the ejection system between the support plate assembly 6 and the rear mold base plate 10, providing sufficient stroke for the reciprocating ejection and resetting of the ejector plate assembly. That is, the ejector plate assembly is located inside the mold foot 7.

[0026] The ejector plate assembly includes an ejector face plate 8 and an ejector base plate 9, which are composed of two stacked plates and installed in the cavity formed inside the mold foot 7. Its function is to fix the reciprocating rod 15 of the unscrew mechanism. The rear mold base plate 10 is the bottommost component of the rear mold assembly. Its function is to fix the entire rear mold assembly to the moving mold side of the injection molding machine and transmit the mold opening and closing power of the injection molding machine. The rear mold base plate 10 bears the weight of all components of the rear mold and provides a docking reference for the ejector pin of the injection molding machine, ensuring that the ejection power is accurately transmitted to the ejector plate.

[0027] The thread unscrew mechanism includes a reciprocating rod 15, a reciprocating nut 14, a thread insert 11, and a thread sleeve 12. The root of the reciprocating rod 15 is fixedly connected to the ejector plate assembly, so the reciprocating rod 15 can move synchronously with the ejector plate assembly. The reciprocating nut 14 is screwed onto the reciprocating rod 15. The thread insert 11 is located on one side of the reciprocating nut 14, and the two are connected by a gear assembly 13, so that the thread insert 11 can move in conjunction with the reciprocating nut 14. The thread sleeve 12 is screwed onto the outside of the thread insert 11. The cavity formed after the mold is closed is located between the front mold plate 4 and the rear mold push plate 5. The head of the thread insert 11 extends through the rear mold push plate 5 into the cavity.

[0028] Specifically, the root of the riveting rod 15 is fixedly connected to the ejector plate assembly, the riveting nut 14 is rotatably installed in the support plate assembly 6 and can only rotate axially, and the threaded sleeve 12 is fixedly installed in the support plate assembly 6. After the mold is opened, the ejector plate assembly, driven by the ejector rod of the injection molding machine, drives the riveting rod 15 to be ejected towards the front mold. Under the action of the screw connection, the riveting nut 14 rotates relative to the riveting rod 15 around its own axis, and drives the threaded insert 11 to rotate together through the gear assembly 13. While rotating, the threaded insert 11 can also move towards the rear mold through the screw connection with the threaded sleeve 12, so that the head of the threaded insert 11 is disengaged from the product undercut.

[0029] The threaded insert 12 is fixedly installed in the second support plate, the gear assembly 13 is located in the first support plate, and the root of the threaded insert 11 is located in the third support plate. When it moves in the direction of the rear mold, it can also extend into the cavity formed inside the mold foot 7. Since the threaded insert 11 moves a small distance, the gears of the gear assembly 13 can maintain a normal meshing relationship during this process. That is, the distance the threaded insert 11 moves is less than the tooth width of the gears in the gear assembly 13.

[0030] Furthermore, a positioning sleeve 16 is fixedly sleeved at the root of the reciprocating rod 15. The positioning sleeve 16 is located between the ejector plate 8 and the ejector base plate 9. An adjusting block 17 for adjusting the rotational position of the reciprocating rod 15 is also provided inside the ejector base plate 9, and the adjusting block 17 is engaged with the positioning sleeve 16. The positioning sleeve 16 is fixedly connected to the reciprocating rod 15. A toothed ring is provided on the outer side of the positioning sleeve 16. A rack is provided on one side of the adjusting block 17. The rack and the toothed ring mesh with each other, and the adjusting block 17 is fixedly installed between the ejector plate assemblies. The circumferential positioning of the reciprocating rod 15 is achieved through the meshing of the rack and the toothed ring, thereby realizing the adjustment of the rotational position of the reciprocating rod 15.

[0031] Furthermore, the gear assembly 13 includes a driving gear 131 and a driven gear 132 that mesh with each other. The driving gear 131 is fixedly sleeved on the outside of the riveting nut 14, and the driven gear 132 is fixedly sleeved on the outside of the threaded insert 11. When the riveting nut 14 rotates under the drive of the riveting rod 15, the driving gear 131 can rotate synchronously with the riveting nut 14, and the driven gear 132 can rotate synchronously with the threaded insert 11. Since the driving gear 131 and the driven gear 132 mesh with each other, the torque of the riveting nut 14 can be transmitted to the threaded insert 11 through the gear assembly 13, and the tooth width of the driving gear 131 and the driven gear 132 is greater than the distance the threaded insert 11 moves.

[0032] Working principle: After the mold opens, the injection-molded product fits onto the head of the threaded insert 11. Then, the injection molding machine ejector pushes the ejector plate 8, ejector base plate 9, reciprocating rod 15, positioning sleeve 16, and adjusting block 17 together towards the front mold. The drive gear 131 and reciprocating rod nut 14 rotate under the action of the reciprocating rod 15. The drive gear 131 drives the threaded insert 11 to rotate together through the driven gear 132. While rotating, the threaded insert 11 moves towards the rear mold through the threaded sleeve 12 and finally disengages from the product undercut. After the threaded insert 11 disengages from the product undercut, the thread unscrewing mechanism stops, and the injection molding machine ejector continues to push the rear mold push plate 5. The product is ejected under the action of the rear mold push plate 5 and then falls freely. The thread unscrewing mechanism is pulled back to its original position by the injection molding machine ejector before the mold closes.

[0033] Example 2, as Figure 1 As shown, based on Embodiment 1, the mold proposed in this utility model is equipped with two sets of unscrew mechanisms. The two sets of unscrew mechanisms are symmetrically distributed inside the rear mold assembly, which can be applied to the injection molding of two-color molds.

[0034] In Example 3, based on Example 1 or Example 2, each set of thread unscrewing mechanism is provided with multiple thread inserts 11. The multiple thread inserts 11 are arranged in a circular array around the axis of the rifling rod 15. Therefore, in each set of thread unscrewing mechanism, only one set of rifling rod 15 and rifling nut 14 is needed to drive multiple sets of thread inserts 11 to rotate and move, which greatly improves the demolding efficiency of the mold.

[0035] like Figure 2 As shown, each set of thread inserts 11 in the thread removal mechanism is equipped with a set of riveting rods 15 and riveting nuts 14 to achieve drive, which is suitable for demolding of products with one cavity and four parts.

[0036] In summary, this utility model proposes a mold with a novel thread unwinding mechanism. The ejector plate assembly drives the rewinding rod 15 to move relative to the rewinding nut 14, converting the linear motion of the rewinding rod 15 into the rotational motion of the rewinding nut 14. The rewinding nut 14 then drives the thread insert 11 to rotate via the gear assembly 13. Furthermore, under the action of the thread sleeve 12, the thread insert 11 can move towards the rear mold while rotating, disengaging from the product undercut without requiring an additional power source. Its compact layout reduces mold size and eliminates the need for conventional thread unwinding mechanisms such as hydraulic cylinders or servo motors. It is particularly suitable for two-color molds where the product has threads but cannot accommodate hydraulic cylinders or servo motors.

[0037] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0038] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0039] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0040] Based on the preferred embodiments of this utility model described above, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A mold with a novel thread-unscrew mechanism, characterized in that: The mold includes a front mold assembly, a rear mold assembly, and a thread unscrewing mechanism disposed within the rear mold assembly. The front mold assembly includes a front template, and the rear mold assembly includes a rear mold push plate, a support plate assembly, and an ejector plate assembly arranged sequentially from front to back. After the mold is closed, a cavity is formed between the front template and the rear mold push plate. The thread unscrew mechanism includes a reciprocating rod that can move synchronously with the ejector plate assembly. A reciprocating nut is screwed onto the reciprocating rod. The reciprocating nut is located within the support plate assembly. A threaded insert that can rotate in conjunction with the reciprocating nut is provided on one side of the reciprocating nut. The threaded insert and the reciprocating nut are connected by a gear assembly. A threaded sleeve is screwed onto the outer side of the threaded insert. The head of the threaded insert extends through the rear mold push plate into the cavity.

2. The mold with a novel unscrew mechanism according to claim 1, characterized in that: The root of the riveting rod is fixedly connected to the ejector plate assembly, the riveting nut is rotatably installed in the support plate assembly, and the threaded sleeve is fixedly installed in the support plate assembly.

3. The mold with a novel unscrew mechanism according to claim 2, characterized in that: The gear assembly includes a driving gear and a driven gear that mesh with each other. The driving gear is fixedly sleeved on the outside of the riveting nut, and the driven gear is fixedly sleeved on the outside of the threaded insert.

4. The mold with a novel unscrew mechanism according to claim 1, characterized in that: The ejector plate assembly includes an overlapping ejector plate and an ejector base plate. A positioning sleeve is fixedly sleeved at the root of the reciprocating rod, and the positioning sleeve is disposed between the ejector plate and the ejector base plate.

5. The mold with a novel unscrew mechanism according to claim 4, characterized in that: The base plate of the ejector pin is also provided with an adjustment block for adjusting the rotation position of the reciprocating rod, and the adjustment block is engaged with the positioning sleeve.

6. The mold with a novel unscrew mechanism according to claim 5, characterized in that: The support plate assembly includes a first support plate, a second support plate, and a third support plate arranged sequentially from front to back. The threaded sleeve is fixedly installed in the second support plate, the gear assembly is located in the first support plate, and the root of the threaded insert is located in the third support plate.

7. The mold with a novel unscrew mechanism according to claim 6, characterized in that: The front mold plate is provided with a hot runner plate, a front mold plate and a heat insulation plate in sequence from back to front on the side opposite to the rear mold push plate, and the ejector plate assembly is provided with a rear mold bottom plate on the side opposite to the rear mold push plate.

8. The mold with a novel unscrew mechanism according to claim 7, characterized in that: A mold foot is provided between the support plate assembly and the rear mold base plate, and the ejector plate assembly is located inside the mold foot.

9. The mold with a novel unscrew mechanism according to claim 1, characterized in that: Two sets of the unscrew mechanism are provided, and the two sets of the unscrew mechanism are symmetrically distributed in the rear mold assembly.

10. The mold with a novel unscrew mechanism according to claim 9, characterized in that: Each of the aforementioned unscrewing mechanisms is provided with multiple thread inserts, which are arranged in a circular array around the axis of the reciprocating rod.

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