An injection mold tooth pinching mechanism

Abstract

The utility model discloses a kind of injection mold tooth twisting mechanisms, it include: sliding block;Tooth twisting unit, it is set in sliding block, its tooth twisting insert extends sliding block surface;Rear mould base, it is set in the side of front mould;Rear mould core, it is set on rear mould base, the end face of directly facing tooth twisting insert;The rear mould core directly facing tooth twisting insert is equipped with a containing clamping groove;Rotary insert, it is set in the containing clamping groove of rear mould core, can freely rotate around the axis of tooth twisting insert, end face and rear mould core surface flush;After the sliding block and rear mould base close mould, rotary insert surface and tooth twisting insert end face impact wear;When the tooth twisting insert starts demolding under the control of tooth twisting unit, tooth twisting insert drives rotary insert synchronous rotation, until tooth twisting insert and rotary insert no longer mutual extrusion contact.The utility model can improve production efficiency, reduce mould maintenance frequency.

Description

Technical Field

[0001] This utility model relates to the field of injection mold design, specifically to an injection mold threading mechanism. Background Technology

[0002] When injection-molded products have threaded holes, threaded inserts need to be designed in the mold to facilitate injection molding and demolding of the threaded holes. (See attached diagram in the instruction manual.) Figure 1-3 As shown, when both ends of the threaded hole are through holes, the threaded insert in a conventional mold is designed to abut against the surface of other mold cores, thereby opening the other end.

[0003] The aforementioned coiled thread insert design has the following problems in practical application: During the mold closing process, the end face of the coiled thread insert needs to be in close contact with other mold cores to prevent injection molding fluid from entering the contact surface and ensure the cleanliness of the threaded hole end face. During mold opening, the coiled thread insert needs to spiral back relative to the injection molded product. At this time, the end face of the coiled thread insert will rotate and rub against other mold cores, causing wear on the coiled thread insert and the other mold cores it contacts. As a result, after mold closing, the end face of the coiled thread insert cannot make close contact with the corresponding other mold core surfaces, and some injection molding fluid flows into the gaps. This requires manual processing of the injection molded product (removal of burrs and flash) or frequent replacement of these two worn parts.

[0004] If we choose to replace worn parts, it will result in high costs and severely impact production efficiency. However, if we do not replace worn parts and manually process injection molded products with burrs or scratches on the threaded holes, it will be impossible for manual processing to handle all the injection molded products that need processing in time during the injection molding production line. Some unprocessed injection molded products will enter the next process, reducing the final product qualification rate. Utility Model Content

[0005] In view of the above-mentioned defects of the prior art, the purpose of this utility model is to provide a screw thread mechanism for injection molds, which can improve production efficiency and reduce the frequency of mold maintenance.

[0006] The objective of this utility model is achieved through the following technical solution:

[0007] A threaded injection mold mechanism, comprising:

[0008] slider;

[0009] A coiled tooth unit is disposed in the slider, and its coiled tooth insert extends out of the slider surface;

[0010] The rear mold base is located on one side of the front mold;

[0011] The rear mold core is set on the rear mold base, facing the end face of the coiled tooth insert; the rear mold core is provided with a receiving slot facing the coiled tooth insert.

[0012] The rotating insert is set in the receiving slot of the rear mold core and can rotate freely around the axis of the coiled tooth insert. Its end face is flush with the surface of the rear mold core. After the slider and the rear mold base are closed, the surface of the rotating insert and the end face of the coiled tooth insert are contacted. When the coiled tooth insert begins to demold under the control of the coiled tooth unit, the coiled tooth insert drives the rotating insert to rotate synchronously until the coiled tooth insert and the rotating insert no longer squeeze and contact each other.

[0013] Furthermore, the rear mold core includes:

[0014] A rear mold insert is mounted on a rear mold base and located outside the coiled thread insert. A platform surface is provided on the rear mold insert directly opposite the end face of the coiled thread insert. The plane of the platform surface is collinear with the axis of the coiled thread insert. The width of the platform surface in the direction perpendicular to the axis of the coiled thread insert is greater than the diameter of the end face of the coiled thread insert. The projection of the end face of the coiled thread insert, extended along its axis, passes through the platform surface. A lower receiving notch is provided on the platform surface directly opposite the end face of the coiled thread insert. The notch of the lower receiving notch is directly opposite the end face of the coiled thread insert.

[0015] The rear mold insert has a mating surface on its lower surface that corresponds to the platform surface; the mating surface has an upper accommodating notch that corresponds to the lower accommodating notch; the notch of the upper accommodating notch faces the end face of the coiled thread insert; when the mating surface of the rear mold insert is mated and fixed to the platform surface of the rear mold insert, the lower accommodating notch and the upper accommodating notch form an accommodating locking groove.

[0016] Furthermore, the lower receiving notch includes:

[0017] The limiting arc groove is semi-cylindrical and recessed on the platform surface;

[0018] The accommodating arc-shaped groove is semi-cylindrical and recessed on the platform surface; the accommodating arc-shaped groove is coaxially connected with the limiting accommodating groove; the side of the accommodating arc-shaped groove is exposed.

[0019] Furthermore, the upper receiving notch structure is the same as the lower receiving notch structure;

[0020] The upper and lower accommodating notches have corresponding limiting arc grooves that face each other, forming a cylindrical limiting cavity; the upper and lower accommodating notches have corresponding accommodating arc grooves that face each other, forming a cylindrical accommodating cavity.

[0021] Furthermore, the rotating insert includes:

[0022] The limiting part is cylindrical and is disposed inside the limiting cavity, with its outer surface in sliding contact with the inner surface of the limiting cavity.

[0023] The receiving part is cylindrical and is disposed in the receiving cavity. It is coaxially connected with the limiting part, and its outer surface slides in contact with the inner surface of the receiving cavity. The outer end face of the receiving part is exposed. When the slider and the rear mold base are closed, the outer end face of the receiving part penetrates the end face of the threaded insert.

[0024] Furthermore, the inner surfaces of the limiting cavity and the receiving cavity are coated with a friction-reducing lubricating material.

[0025] Furthermore, the platform surface of the rear mold insert is provided with at least two lower pin holes, and the mating surface of the rear mold insert is provided with upper pin holes; after the mating surface of the rear mold insert is mated and fixed to the platform surface of the rear mold insert, the lower pin holes and the upper pin holes are coaxial.

[0026] The rear mold core also includes pins corresponding to the number of lower pin holes; the mating surface of the rear mold insert is mated to the platform surface of the rear mold insert by positioning with pins.

[0027] Furthermore, the mating surface of the rear mold insert and the platform surface of the rear mold insert are positioned and mated together by pins and then welded together.

[0028] Furthermore, the coilover unit includes:

[0029] A rotating mechanism is mounted on the slider;

[0030] The drive gear is rotatably mounted inside the slider and is coaxially connected to the output end of the rotating mechanism;

[0031] The driven gear is rotatably mounted inside the slider and meshes with the driving gear;

[0032] The control shaft is coaxially inserted into the driven gear, meshing with the driven gear circumferentially and sliding axially; the control shaft is slidably connected to the slider along its axis.

[0033] The coiled insert is coaxially mounted at the head end of the control shaft.

[0034] Furthermore, the control shaft is provided with a protruding limiting ring, and the slider is provided with a sliding cavity for the limiting ring to move when the control shaft moves back and forth along its axial direction.

[0035] Due to the adoption of the above technical solution, this utility model has the following advantages:

[0036] 1. Make simple modifications to the existing mold, and change the mold core that is directly opposite the coiled tooth insert to a rotating insert that can rotate synchronously with the coiled tooth insert. This will prevent the end face of the coiled tooth insert and the corresponding mold core area from being worn due to relative rotational friction during the mold opening process.

[0037] 2. By setting a rotating insert and a matching receiving slot, the area of ​​rotational friction is adjusted to be within the receiving slot. The friction coefficient between the rotating insert and the receiving slot can be reduced by means of lubricating grease, thus reducing frictional damage. This solves the problem in conventional mold solutions where the end face of the threaded insert and its corresponding mold core area must be clean (uncleanliness can easily lead to mutual contact and compression without compaction, and the injection liquid can enter between the two during the injection process, forming a separation edge), resulting in abnormal wear.

[0038] 3. The technical solution of this utility model can significantly reduce the frequency of mold maintenance, and even eliminate the need to replace certain parts of the mold, requiring only the application of lubricating grease. Overall, the reduced maintenance frequency and time ensure the quality of the internal thread end face of the injection molded product.

[0039] Other advantages, objectives and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be taught from the practice of this invention. Attached Figure Description

[0040] The accompanying drawings of this utility model are described below:

[0041] Figure 1 A front view structural diagram of an injection-molded product with an internally threaded hole.

[0042] Figure 2 This is a first three-dimensional structural diagram of an injection-molded product with an internally threaded hole.

[0043] Figure 3 This is a schematic diagram of the second three-dimensional structure of an injection-molded product with an internally threaded hole.

[0044] Figure 4 This is a three-dimensional structural diagram of the injection mold threading mechanism in the embodiment.

[0045] Figure 5 for Figure 4 Enlarged structural diagram at point A in the middle.

[0046] Figure 6 This is a top view of the screw thread mechanism of the injection mold in the embodiment.

[0047] Figure 7 for Figure 6Schematic diagram of the structure at the BB section.

[0048] Figure 8 for Figure 7 Enlarged structural diagram at point C.

[0049] Figure 9 for Figure 7 Enlarged structural diagram at point D.

[0050] Figure 10 This is a three-dimensional structural diagram of the injection mold threading mechanism (hidden slider part structure, rear mold insert, pin) in the embodiment.

[0051] Figure 11 for Figure 10 Enlarged structural diagram at point E in the middle.

[0052] Figure 12 This is a front view schematic diagram of the rear mold insert in the embodiment.

[0053] Figure 13 This is a three-dimensional structural diagram of the rear mold insert in the embodiment.

[0054] Figure 14 This is a front view of the structure after the rear mold insert is fitted with pins in the embodiment.

[0055] Figure 15 This is a three-dimensional structural diagram of the rear mold insert after the pins are installed in the embodiment.

[0056] In the diagram: 1. Slider; 11. Sliding cavity; 21. Rotating mechanism; 22. Driving gear; 23. Driven gear; 24. Control shaft; 241. Limiting ring; 25. Twisted insert; 3. Rear mold base; 41. Rear mold insert; 411. Platform surface; 412. Lower receiving notch; 413. Lower pin hole; 42. Rear mold insert; 421. Mating surface; 422. Upper receiving notch; 423. Upper pin hole; 43. Limiting arc groove; 44. Receiving arc groove; 45. Pin; 5. Rotating insert; 51. Limiting part; 52. Receiving part; 6. Injection molded product; 61. Threaded hole. Detailed Implementation

[0057] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0058] Example:

[0059] like Figures 4 to 15 As shown, a threaded joint mechanism for injection molds includes:

[0060] Slider 1;

[0061] A coiled tooth unit is disposed in the slider 1, and its coiled tooth insert 25 extends out of the surface of the slider 1;

[0062] The rear mold base 3 is located on one side of the front mold;

[0063] The rear mold core is set on the rear mold base 3, facing the end face of the coiled tooth insert 25; the rear mold core is provided with a receiving slot facing the coiled tooth insert 25;

[0064] The rotating insert 5 is set in the receiving slot of the rear mold core and can rotate freely around the axis of the swivel insert 25. Its end face is flush with the surface of the rear mold core. After the slider 1 and the rear mold base 3 are closed, the surface of the rotating insert 5 touches through the end face of the swivel insert 25. When the swivel insert 25 begins to demold under the control of the swivel unit, the swivel insert 25 drives the rotating insert 5 to rotate synchronously until the swivel insert 25 and the rotating insert 5 no longer press against each other.

[0065] By making simple modifications to the existing mold, the mold core directly opposite the coiled tooth insert 25 is transformed into a rotating insert 5 that can rotate synchronously with the coiled tooth insert 25. This prevents wear on the end face of the coiled tooth insert 25 and its corresponding mold core area due to relative rotational friction during the mold opening process.

[0066] In this embodiment, the rear mold core includes:

[0067] A rear mold insert 41 is disposed on the rear mold base 3, located outside the coiled tooth insert 25; a platform surface 411 is provided on the rear mold insert 41 directly opposite the end face of the coiled tooth insert 25; the plane of the platform surface 411 is collinear with the axis of the coiled tooth insert 25; the width of the platform surface 411 in the direction perpendicular to the axis of the coiled tooth insert 25 is greater than the diameter of the end face of the coiled tooth insert 25; the projection of the end face of the coiled tooth insert 25 after its extension in the axial direction passes through the platform surface 411; a lower receiving notch 412 is provided on the platform surface 411 directly opposite the end face of the coiled tooth insert 25; the notch of the lower receiving notch 412 is directly opposite the end face of the coiled tooth insert 25.

[0068] The rear mold insert 42 has a mating surface 421 on its lower surface that corresponds to the platform surface 411; the mating surface 421 has an upper receiving notch 422 that corresponds to the lower receiving notch 412; the notch of the upper receiving notch 422 faces the end face of the coiled insert 25; when the mating surface 421 of the rear mold insert 42 is mated and fixed to the platform surface 411 of the rear mold insert 41, the lower receiving notch 412 and the upper receiving notch 422 form a receiving locking groove.

[0069] Setting the rear mold core as a two-part structure can achieve the purpose of accommodating the rotating insert 5, and at the same time, it can facilitate the maintenance and replacement of the rotating insert 5.

[0070] In this embodiment, the lower receiving notch 412 includes:

[0071] The limiting arc groove 43 is semi-cylindrical and recessed on the platform surface 411;

[0072] The accommodating arc-shaped groove 44 is semi-cylindrical and concavely disposed on the platform surface 411; the accommodating arc-shaped groove 44 is coaxially connected with the limiting accommodating groove; the side of the accommodating arc-shaped groove 44 is exposed.

[0073] The structure of the upper receiving notch 422 is the same as that of the lower receiving notch 412;

[0074] The upper accommodating notch 422 and the lower accommodating notch 412 have opposing limiting arc grooves 43, forming a cylindrical limiting cavity; the upper accommodating notch 422 and the lower accommodating notch 412 have opposing accommodating arc grooves 44, forming a cylindrical accommodating cavity.

[0075] The rotating insert 5 includes:

[0076] The limiting part 51 is cylindrical and is disposed in the limiting cavity, with its outer surface in sliding contact with the inner surface of the limiting cavity.

[0077] The receiving part 52 is cylindrical and is disposed in the receiving cavity. It is coaxially connected with the limiting part 51, and its outer surface slides in contact with the inner surface of the receiving cavity. The outer end face of the receiving part 52 is exposed. When the slider 1 and the rear mold base 3 are closed, the outer end face of the receiving part 52 penetrates the end face of the threaded insert 25.

[0078] Setting the rotating insert 5 to a T-shaped structure can ensure that it can withstand forces well (transmit the extrusion force of the coiled insert 25) and that it will not detach from the rear mold core during the mold opening process as the coiled insert 25 moves.

[0079] In this embodiment, the inner surfaces of the limiting cavity and the accommodating cavity are coated with a friction-reducing lubricating material.

[0080] The coefficient of friction between the rotating insert 5 and the receiving slot can be reduced by means of lubricating grease or other methods, thereby reducing frictional damage.

[0081] In this embodiment, the platform surface 411 of the rear mold insert 41 is provided with at least two lower pin holes 413, and the mating surface 421 of the rear mold insert 42 is provided with upper pin holes 423; after the mating surface 421 of the rear mold insert 42 is mated and fixed with the platform surface 411 of the rear mold insert 41, the lower pin holes 413 and the upper pin holes 423 are coaxial.

[0082] The rear mold core also includes pins 45 corresponding to the number of lower pin holes 413; the mating surface 421 of the rear mold insert 42 and the platform surface 411 of the rear mold insert 41 are mated by the pins 45 for positioning.

[0083] To ensure a smooth injection surface of the product formed after the connection between the rear mold insert 41 and the rear mold block 42, a positioning pin 45 is provided.

[0084] In this embodiment, the mating surface 421 of the rear mold insert 42 and the platform surface 411 of the rear mold insert 41 are positioned and mated together by pins 45 and then welded together.

[0085] The technical solution of this utility model can significantly reduce the frequency of mold maintenance, and even eliminate the need to replace certain parts of the mold, requiring only the application of lubricating grease. Overall, the reduced maintenance frequency and shorter maintenance time ensure the quality of the internal thread end face of the injection molded product 6.

[0086] If a good lubricant is used, the rotating insert 5 can be replaced without replacement, that is, the rear mold insert 42 and the rear mold insert 41 can be welded and fixed together. This can improve the surface flatness at the joint between the two and improve the appearance quality of the product.

[0087] In this embodiment, the coiled tooth unit includes:

[0088] Rotation mechanism 21 is mounted on slider 1;

[0089] The drive gear 22 is rotatably mounted inside the slider 1 and is coaxially connected to the output end of the rotating mechanism 21;

[0090] Driven gear 23 is rotatably disposed inside slider 1 and meshes with driving gear 22;

[0091] The control shaft 24 is coaxially inserted into the driven gear 23, meshing with the driven gear 23 circumferentially and sliding axially; the control shaft 24 is slidably connected to the slider 1 along its axis.

[0092] The coiled insert 25 is coaxially disposed at the head end of the control shaft 24.

[0093] The control shaft 24 is provided with a protruding limiting ring 241, and the slider 1 is provided with a sliding cavity 11 for the limiting ring 241 to move when the control shaft 24 moves back and forth along its axial direction.

[0094] By setting up the auger unit, the auger insert 25 can smoothly rotate relative to the insert 5 during the mold opening and closing processes.

[0095] The injection mold threaded mechanism in this embodiment works as follows: Figure 4 All components are installed and secured as shown.

[0096] During mold closing, the control slider 1 and the rear mold base 3 move closer to each other until they reach a predetermined position. Then, other mold closing motion control mechanisms are used to push the control shaft 24 to move towards the rotating insert 5 until the end face of the threaded insert 25 abuts against the end face of the rotating insert 5. At this time, the threaded insert 25 and the rotating insert 5 are in a through-hole state, that is, they are attached together. This completes the mold closing of the threaded mechanism in this application.

[0097] Then, injection molding liquid is injected for injection molding. After injection molding is completed, the compression control of the control shaft 24 towards the rotating insert 5 is first released; then the rotating mechanism 21 (hydraulic cylinder) is started to rotate, which drives the drive gear 22 to rotate, the drive gear 22 drives the driven gear 23 to rotate, and the driven gear 23 drives the control shaft 24 to rotate, causing the coiled insert 25 to rotate and retract into the slider 1 (the control shaft 24 slides relative to its axis under the control of the spline connected to the driven gear 23). At this time, since the coiled insert 25 and the rotating insert 5 are in a fitted state (commonly understood as stuck together), at the initial stage of retraction, the coiled insert 25 will drive the rotating insert 5 to rotate synchronously until the coiled insert 25 retracts to a certain amount, the rotating insert 5 is restricted by the limiting arc groove 43 to move towards the coiled insert 25. At this time, the coiled insert 25 and the rotating insert 5 separate, and finally the coiled insert 25 is completely unscrewed out of the injection molded product 6.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. An injection mold thread pinching mechanism characterized by, include: slider; A coiled tooth unit is disposed in the slider, and its coiled tooth insert extends out of the slider surface; The rear mold base is located on one side of the front mold; The rear mold core is set on the rear mold base, facing the end face of the coiled tooth insert; the rear mold core is provided with a receiving slot facing the coiled tooth insert. The rotating insert is set in the receiving slot of the rear mold core and can rotate freely around the axis of the coiled tooth insert. Its end face is flush with the surface of the rear mold core. After the slider and the rear mold base are closed, the surface of the rotating insert and the end face of the coiled tooth insert are contacted. When the coiled tooth insert begins to demold under the control of the coiled tooth unit, the coiled tooth insert drives the rotating insert to rotate synchronously until the coiled tooth insert and the rotating insert no longer squeeze and contact each other.

2. The injection mold tooth jockey mechanism of claim 1, wherein, The rear mold core includes: A rear mold insert is mounted on a rear mold base and located outside the coiled thread insert. A platform surface is provided on the rear mold insert directly opposite the end face of the coiled thread insert. The plane of the platform surface is collinear with the axis of the coiled thread insert. The width of the platform surface in the direction perpendicular to the axis of the coiled thread insert is greater than the diameter of the end face of the coiled thread insert. The projection of the end face of the coiled thread insert, extended along its axis, passes through the platform surface. A lower receiving notch is provided on the platform surface directly opposite the end face of the coiled thread insert. The notch of the lower receiving notch is directly opposite the end face of the coiled thread insert. The rear mold insert has a mating surface on its lower surface that corresponds to the platform surface; the mating surface has an upper accommodating notch that corresponds to the lower accommodating notch; the notch of the upper accommodating notch faces the end face of the coiled thread insert; when the mating surface of the rear mold insert is mated and fixed to the platform surface of the rear mold insert, the lower accommodating notch and the upper accommodating notch form an accommodating locking groove.

3. The injection mold tooth parting mechanism of claim 2, wherein, The lower accommodating notch includes: The limiting arc groove is semi-cylindrical and recessed on the platform surface; The accommodating arc-shaped groove is semi-cylindrical and recessed on the platform surface; the accommodating arc-shaped groove is coaxially connected with the limiting accommodating groove; the side of the accommodating arc-shaped groove is exposed.

4. The injection mold toothspreading mechanism of claim 3 wherein, The upper accommodating notch structure is the same as the lower accommodating notch structure; The upper and lower accommodating notches have corresponding limiting arc grooves that face each other, forming a cylindrical limiting cavity; the upper and lower accommodating notches have corresponding accommodating arc grooves that face each other, forming a cylindrical accommodating cavity.

5. The injection mold toothspreading mechanism of claim 4 wherein, The rotating insert includes: The limiting part is cylindrical and is disposed inside the limiting cavity, with its outer surface in sliding contact with the inner surface of the limiting cavity. The receiving part is cylindrical and is disposed in the receiving cavity. It is coaxially connected with the limiting part, and its outer surface slides in contact with the inner surface of the receiving cavity. The outer end face of the receiving part is exposed. When the slider and the rear mold base are closed, the outer end face of the receiving part penetrates the end face of the threaded insert.

6. The injection mold toothspreading mechanism of claim 5 wherein, The inner surfaces of the limiting cavity and the receiving cavity are coated with friction-reducing lubricating material.

7. The injection mold threading mechanism according to claim 2, characterized in that, The platform surface of the rear mold insert is provided with at least two lower pin holes, and the mating surface of the rear mold insert is provided with upper pin holes; after the mating surface of the rear mold insert is mated and fixed to the platform surface of the rear mold insert, the lower pin holes and the upper pin holes are coaxial. The rear mold core also includes pins corresponding to the number of lower pin holes; the mating surface of the rear mold insert is mated to the platform surface of the rear mold insert by positioning with pins.

8. The injection mold toothspreading mechanism of claim 7 wherein, The mating surface of the rear mold insert and the platform surface of the rear mold insert are fixed together by welding after being positioned and mated by pins.

9. The injection mold toothspreading mechanism of claim 7 wherein, The coilover unit includes: A rotating mechanism is mounted on the slider; The drive gear is rotatably mounted inside the slider and is coaxially connected to the output end of the rotating mechanism; The driven gear is rotatably mounted inside the slider and meshes with the driving gear; The control shaft is coaxially inserted into the driven gear, meshing with the driven gear circumferentially and sliding axially; the control shaft is slidably connected to the slider along its axis. The coiled insert is coaxially mounted at the head end of the control shaft.

10. The injection mold tooth jockey mechanism of claim 9, wherein, The control shaft is provided with a protruding limiting ring, and the slider is provided with a sliding cavity for the limiting ring to move when the control shaft moves back and forth along its axial direction.

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