A progressive multifocal resin lens molding die
By designing overflow grooves and combining demolding mechanisms on the mold surface, the problems of air bubbles in resin injection and difficult demolding were solved, achieving high-quality molding and efficient production of lenses.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHENJIANG CV OPTICAL CO LTD
- Filing Date
- 2025-06-12
- Publication Date
- 2026-05-26
Smart Images
Figure CN224275982U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of mold technology, specifically relating to a progressive multifocal resin lens molding mold. Background Technology
[0002] In the field of optical lens manufacturing, progressive multifocal resin lenses have become an important product in vision correction due to their ability to achieve clear vision at different distances (far, intermediate, and near) on the same lens. The molding quality of these lenses directly affects their optical performance and wearing comfort, and the structural design of the molding mold is one of the core factors determining lens quality.
[0003] Chinese patent CN202210114139.3 discloses "an easy-to-fit progressive multifocal lens, its manufacturing method, and a mold. The effective visual area around the progressive meridian of the lens is divided into five regions according to the different distances of the observed object: a distance aspherical region, a central fixation region, a mid-distance continuous visual transition zone, a reading buffer zone, and a stable reading zone; the progressive changes in optical power in each region are reasonably distributed, effectively balancing the functionality and comfort of the lens." On the one hand, the injection molding structure of the mold typically uses a single-point or limited-point resin injection method, resulting in uneven resin flow within the mold cavity (i.e., the core area). This easily leads to air stagnation areas inside the core, resulting in air bubbles. These air bubbles not only damage the optical uniformity of the lens but may also reduce lens strength, affecting product yield. On the other hand, the demolding mechanism of traditional molds is often rudimentary, relying heavily on manual assistance or simple ejection structures. After the resin lens is formed, the demolding process easily causes scratches or deformation to the lens surface, especially for complex-shaped progressive multifocal lenses, making demolding even more difficult and further reducing production efficiency and product quality. Utility Model Content
[0004] This utility model addresses the shortcomings of existing technologies by providing a progressive multifocal resin lens molding die, the specific technical solution of which is as follows:
[0005] A progressive multifocal resin lens molding die includes a support frame, a hydraulic push rod mounted in the middle of the support frame, a support rod fixed to the telescopic end of the hydraulic push rod, a lower mold fixed to the upper surface of the support rod, an upper mold above the lower mold, a lower mold core on the upper surface of the lower mold, an upper mold core on the lower surface of the upper mold, overflow grooves on both the upper and lower surfaces of the lower and upper molds, with the overflow groove on the upper surface of the lower mold communicating with the lower mold core and the overflow groove on the lower surface of the upper mold communicating with the upper mold core, four injection tubes communicating with the upper mold core mounted on the upper surface of the upper mold, a demolding mechanism for demolding provided inside the lower mold core, and a pressure regulating component for filling the lower and upper mold cores with resin in the middle of the lower mold.
[0006] Preferably, the demolding mechanism includes a push block movably installed inside the lower mold core, a guide rod fixed on the lower surface of the push block and passing through the lower mold, a tension spring fixed inside the lower mold core and the two ends of the tension spring respectively fixed between the push block and the lower mold core, and a limiting ring for supporting the push block integrally formed on the inner surface of the lower mold core.
[0007] Preferably, the pressure regulating component includes an overflow pipe opened in the middle of the lower mold, and the overflow pipe is connected to the lower mold core and the upper mold core respectively through an overflow groove. A pressure regulating plate is movably installed inside the overflow pipe. Three limiting rods are fixed on the lower surface of the pressure regulating plate. Three guide tubes are fixed at the bottom of the overflow pipe. The lower end of the limiting rod is movably installed inside the upper end of the guide tube, and the guide tube and the limiting rod correspond one-to-one. A compressed return spring is fixed inside the overflow pipe, and the upper end of the return spring is fixed on the lower surface of the pressure regulating plate.
[0008] Preferably, the lower end of the overflow pipe penetrates the lower surface of the lower mold.
[0009] Preferably, four guide rods are fixed at the four corners of the upper surface of the bracket, and guide holes are provided at the four corners of the lower mold and the upper mold, with the guide rods movably installed inside the guide holes.
[0010] Compared with the prior art, the beneficial effects of this utility model are:
[0011] 1. The overflow grooves on the upper and lower surfaces of the lower mold allow the lower mold core on the upper surface of the lower mold and the upper mold core on the lower surface of the upper mold to be connected through the overflow grooves. This facilitates the injection of resin into the upper mold core through the four injection tubes. The resin then flows from the outside to the center through the overflow grooves and converges at the pressure regulating component. This ensures that the resin injected into the lower and upper mold cores remains full, thus preventing air bubbles from forming. The lower mold core is equipped with a demolding mechanism for easy demolding after the resin in the lower mold core has been molded.
[0012] 2. The demolding mechanism consists of a push block, a guide rod, a tension spring, and a limiting ring. The lower surface of the push block, which is movably installed inside the lower mold core, is fixed with a guide rod. The guide rod passes through the lower mold, so that when the hydraulic push rod retracts, it brings the lower mold closer to the support. This allows the support to press the guide rod, causing the guide rod to move the push block upward. The resin lens formed inside the lower mold core is then lifted by the push block. As the push block moves upward, the tension spring continues to stretch, causing the guide rod to separate from the support. The push block then resets under the action of the tension spring.
[0013] 3. A pressure regulating component consisting of an overflow pipe, a pressure regulating plate, a guide pipe, a limit rod, and a return spring is used. The pressure regulating plate is movably installed in the overflow pipe in the middle of the lower mold. The overflow pipe is connected to the lower mold core and the upper mold core through an overflow groove, so that excess resin after the lower mold core and the upper mold core are injected can flow into the overflow pipe through the overflow groove. As the amount of resin in the overflow pipe increases, it moves the pressure regulating plate downward. At the same time, the pressure regulating plate compresses the return spring after displacement. After displacement, the limit rod moves at the upper end of the guide pipe, thereby increasing the stability of the pressure regulating plate during displacement. Attached Figure Description
[0014] Figure 1 This is a three-dimensional structural diagram of the present invention;
[0015] Figure 2 This is a schematic diagram of the unfolded structure of this utility model;
[0016] Figure 3 This is a schematic diagram of a half-section of the present invention;
[0017] Figure 4 for Figure 3 A magnified structural diagram of point A in the middle.
[0018] Reference numerals: 1. Bracket; 2. Hydraulic push rod; 3. Lower mold; 4. Upper mold; 5. Guide rod; 6. Guide hole; 7. Lower mold core; 8. Upper mold core; 9. Push block; 10. Guide rod; 11. Tension spring; 12. Limiting ring; 13. Injection tube; 14. Overflow groove; 15. Overflow pipe; 16. Pressure regulating plate; 17. Guide tube; 18. Limiting rod; 19. Return spring; 20. Support rod. Detailed Implementation
[0019] The technical solution of this utility model will now be described with reference to the accompanying drawings and embodiments.
[0020] Please see Figure 1-4 This embodiment provides the following technical solution: A progressive multifocal resin lens molding die includes a bracket 1, a hydraulic push rod 2 installed in the middle of the bracket 1, a support rod 20 fixed at the telescopic end of the hydraulic push rod 2, a lower mold 3 fixed on the upper surface of the support rod 20, an upper mold 4 arranged above the lower mold 3, a lower mold core 7 opened on the upper surface of the lower mold 3, an upper mold core 8 opened on the lower surface of the upper mold 4, overflow grooves 14 opened on the upper surface of the lower mold 3 and the lower surface of the upper mold 4, and the overflow grooves 14 opened on the upper surface of the lower mold 3 are connected to the lower mold core 7, and the overflow grooves 14 opened on the lower surface of the upper mold 4 are connected to the upper mold core 8, four injection tubes 13 connected to the upper mold core 8 are installed on the upper surface of the upper mold 4, a demolding mechanism for demolding is provided in the lower mold core 7, and a pressure regulating component for filling the lower mold core 7 and the upper mold core 8 with resin is provided in the middle of the lower mold 3.
[0021] In this embodiment, the overflow grooves 14 formed on the upper surface of the lower mold 3 and the lower surface of the upper mold 4 allow the lower mold core 7 formed on the upper surface of the lower mold 3 and the upper mold core 8 formed on the lower surface of the upper mold 4 to be connected through the overflow grooves 14. This facilitates the injection of resin into the upper mold core 8 by the four injection tubes 13, with the resin flowing from the outside to the center through the overflow grooves 14 to the pressure regulating component. This ensures that the resin injected into the lower mold core 7 and the upper mold core 8 remains full, thus preventing air bubbles from forming in the resin injected into the lower mold core 7 and the upper mold core 8. The lower mold core 7 is provided with a demolding mechanism for demolding, which facilitates demolding after the resin in the lower mold core 7 has been molded.
[0022] Specifically, the demolding mechanism includes a push block 9 movably installed inside the lower mold core 7, a guide rod 10 fixed on the lower surface of the push block 9, and the guide rod 10 passes through the lower mold 3. A tension spring 11 is fixed inside the lower mold core 7, and the two ends of the tension spring 11 are respectively fixed between the push block 9 and the lower mold core 7. A limiting ring 12 for supporting the push block 9 is integrally formed on the inner surface of the lower mold core 7.
[0023] In this embodiment, a demolding mechanism consisting of a push block 9, a guide rod 10, a tension spring 11, and a limiting ring 12 is used. The lower surface of the push block 9, which is movably installed inside the lower mold core 7, is fixed with a guide rod 10. The guide rod 10 passes through the lower mold 3, so that when the extension end of the hydraulic push rod 2 retracts, the hydraulic push rod 2 carries the lower mold 3 closer to the bracket 1, thereby enabling the bracket 1 to press the guide rod 10, and enabling the guide rod 10 to move the push block 9 upward. This allows the resin lens formed inside the lower mold core 7 to be lifted by the action of the push block 9. When the push block 9 moves upward, the tension spring 11 continues to stretch, so that after the guide rod 10 separates from the bracket 1, the push block 9 resets under the action of the tension spring 11.
[0024] Specifically, the pressure regulating component includes an overflow pipe 15 opened in the middle of the lower mold 3, and the overflow pipe 15 is connected to the lower mold core 7 and the upper mold core 8 respectively through the overflow groove 14. A pressure regulating plate 16 is movably installed inside the overflow pipe 15. Three limit rods 18 are fixed on the lower surface of the pressure regulating plate 16. Three guide tubes 17 are fixed at the bottom of the overflow pipe 15. The lower end of the limit rod 18 is movably installed inside the upper end of the guide tube 17, and the guide tube 17 and the limit rod 18 correspond one-to-one. A compressed return spring 19 is fixed inside the overflow pipe 15, and the upper end of the return spring 19 is fixed on the lower surface of the pressure regulating plate 16. The lower end of the overflow pipe 15 penetrates the lower surface of the lower mold 3 to facilitate venting.
[0025] In this embodiment, a pressure regulating component consisting of an overflow pipe 15, a pressure regulating plate 16, a guide pipe 17, a limiting rod 18, and a return spring 19 is used. The pressure regulating plate 16 is movably installed inside the overflow pipe 15 in the middle of the lower mold 3. At the same time, the overflow pipe 15 is connected to the lower mold core 7 and the upper mold core 8 through the overflow groove 14, so that after the lower mold core 7 and the upper mold core 8 are injected with resin, the excess resin flows into the interior of the overflow pipe 15 through the overflow groove 14. As the amount of resin in the overflow pipe 15 increases, it causes the pressure regulating plate 16 to move downward. At the same time, after the pressure regulating plate 16 moves, it compresses the return spring 19. After the pressure regulating plate 16 moves, the limiting rod 18 moves at the upper end of the guide pipe 17, thereby increasing the stability of the pressure regulating plate 16 during displacement.
[0026] Specifically, four guide rods 5 are fixed at the four corners of the upper surface of the bracket 1. Guide holes 6 are provided at the four corners of the lower mold 3 and the upper mold 4, and the guide rods 5 are movably installed inside the guide holes 6, which facilitates the cooperation between the guide rods 5 and the guide holes 6 and increases the stability of the lower mold 3 and the upper mold 4 when they move.
[0027] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A progressive multifocal resin lens molding die, comprising a bracket (1), wherein a hydraulic push rod (2) is mounted in the middle of the bracket (1), a support rod (20) is fixed to the telescopic end of the hydraulic push rod (2), a lower mold (3) is fixed to the upper surface of the support rod (20), an upper mold (4) is disposed above the lower mold (3), a lower mold core (7) is provided on the upper surface of the lower mold (3), and an upper mold core (8) is provided on the lower surface of the upper mold (4), characterized in that: Overflow grooves (14) are provided on the upper surface of the lower mold (3) and the lower surface of the upper mold (4). The overflow groove (14) on the upper surface of the lower mold (3) is connected to the lower mold core (7), and the overflow groove (14) on the lower surface of the upper mold (4) is connected to the upper mold core (8). Four injection tubes (13) connected to the upper mold core (8) are installed on the upper surface of the upper mold (4). A demolding mechanism for demolding is provided in the lower mold core (7). A pressure regulating component for filling the lower mold core (7) and the upper mold core (8) with resin is provided in the middle of the lower mold (3).
2. The progressive multifocal resin lens molding die according to claim 1, characterized in that: The demolding mechanism includes a push block (9) movably installed inside the lower mold core (7). A guide rod (10) is fixed on the lower surface of the push block (9) and the guide rod (10) passes through the lower mold (3). A tension spring (11) is fixed inside the lower mold core (7) and the two ends of the tension spring (11) are respectively fixed between the push block (9) and the lower mold core (7). A limiting ring (12) for supporting the push block (9) is integrally formed on the inner surface of the lower mold core (7).
3. The progressive multifocal resin lens molding die according to claim 1, characterized in that: The pressure regulating component includes an overflow pipe (15) opened in the middle of the lower mold (3), and the overflow pipe (15) is connected to the lower mold core (7) and the upper mold core (8) respectively through the overflow groove (14). A pressure regulating plate (16) is movably installed in the overflow pipe (15). Three limiting rods (18) are fixed on the lower surface of the pressure regulating plate (16). Three guide tubes (17) are fixed at the bottom of the overflow pipe (15). The lower end of the limiting rod (18) is movably installed inside the upper end of the guide tube (17), and the guide tube (17) and the limiting rod (18) correspond one to one. A compressed return spring (19) is fixed in the overflow pipe (15), and the upper end of the return spring (19) is fixed on the lower surface of the pressure regulating plate (16).
4. The progressive multifocal resin lens molding die according to claim 3, characterized in that: The lower end of the overflow pipe (15) penetrates the lower surface of the lower mold (3).
5. The progressive multifocal resin lens molding die according to claim 1, characterized in that: Four guide rods (5) are fixed at the four corners of the upper surface of the bracket (1). Guide holes (6) are opened at the four corners of the lower mold (3) and the upper mold (4), and the guide rods (5) are movably installed inside the guide holes (6).