A device and method for injection molding male and female contact lens shells using a common mold.

Abstract

This invention provides a co-molding apparatus and method for male and female contact lens shells, comprising an upper mold and a lower mold. The upper mold consists of an upper fixed plate, a female mold core, and a female mold pressure block, while the lower mold consists of a lower fixed plate, a male mold core, and a top block. The female and male mold cores are precisely positioned using 0° positioning blocks, 0° positioning grooves, guide sleeves, and guide pillars to ensure the fitting accuracy between the molds. The mold is equipped with an injection flow channel and a cooling water system to control material flow and mold temperature during injection molding, reducing shell deformation. The invention also includes precise positioning of the female and male mold cores, the injection molding process, mold cooling temperature control, and finished product numbering and quality inspection. By optimizing the mold structure and injection molding process, the matching accuracy of male and female contact lens shells, production efficiency, and finished product quality stability are improved, reducing the defect rate and enhancing product traceability and management. This technical solution helps improve the comfort, oxygen permeability, and visual effect of contact lenses, thereby enhancing market competitiveness.

Description

Technical Field

[0001] This invention relates to the field of contact lens shell and membrane processing technology, specifically to a co-mold injection molding apparatus and method for contact lens shells and membranes. Background Technology

[0002] Contact lenses are widely used vision correction products, typically made of special materials for comfortable wear and to meet daily needs. Their structure usually includes a shell made of rigid or soft materials to cover the eye, protecting and correcting vision. The shell of a contact lens is usually composed of two parts: a male mold and a female mold, produced through injection molding. The precision of the fit between the male and female molds directly affects the comfort, oxygen permeability, visual quality, and wearing effect of the contact lens.

[0003] Traditional methods for molding male and female contact lens shells primarily utilize injection molding technology, employing single-mold or multi-mold production methods. The molding of the male and female molds typically relies on manual or mechanical positioning and assembly, which carries a certain risk of error. This can lead to dimensional deviations and inaccurate matching of the shells, thus affecting product quality and comfort. To improve production efficiency and finished product quality, injection molding equipment and processes require further optimization. Summary of the Invention

[0004] To address the aforementioned technical shortcomings, the purpose of this invention is to provide a co-molding apparatus and method for male and female contact lens shells, thereby improving molding efficiency and enhancing matching accuracy.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An injection molding apparatus and method for male and female contact lens shells using a common mold, comprising an upper mold and a lower mold;

[0007] The upper mold includes an upper fixed plate, a female mold core, and a female mold pressing block; the female mold core is placed between the upper fixed plate and the female mold pressing block; the female mold pressing block is fixedly connected to the upper fixed plate, fixing the female mold core on the upper fixed plate; the female mold core is provided with a female mold insert and a male mold insert;

[0008] The lower mold includes a lower fixed plate, a male mold core, and an ejector block; the male mold core is placed between the lower fixed plate and the ejector block; the ejector block is fixedly connected to the lower fixed plate, fixing the male mold core on the lower fixed plate; the male mold core is provided with male mold inserts and female mold inserts that mate with female mold inserts and male mold inserts on the female mold core; injection runners are provided on the female mold pressure block and the ejector block.

[0009] Preferably, both the upper and lower fixing plates are provided with cooling water channels.

[0010] Preferably, both the upper fixing plate and the lower fixing plate are provided with code hole.

[0011] Preferably, the female mold core is provided with a 0° positioning block, and the male mold core is provided with a 0° positioning groove that cooperates with the 0° positioning block.

[0012] Preferably, the female mold core is provided with a guide sleeve; the male mold core is fixedly provided with a guide post adapted to the guide sleeve.

[0013] A method for producing male and female contact lens shells using a co-mold injection molding apparatus includes the following steps:

[0014] a) The female mold core is fixed on the upper fixing plate by the female mold pressure block;

[0015] b) Fix the male mold core to the lower fixing plate using the top block;

[0016] c) The male and female mold plates are precisely installed and fitted using guide sleeves and guide posts, and the male and female mold cores are precisely positioned using 0° positioning blocks and 0° positioning grooves;

[0017] d) Start the injection molding process on the injection molding machine to simultaneously produce male and female shell films;

[0018] e) Cooling and temperature control are achieved through an internal water system in the mold;

[0019] f) Remove the completed male and female shell membranes and transfer them to the next process.

[0020] Preferably, the injection molding process includes the following steps:

[0021] a) Set the temperature, pressure, injection speed, and cooling time of the injection molding machine according to the material of the contact lens shell;

[0022] b) After the mold is closed, the molten material is injected into the mold cavity through the injection molding machine, forming male and female shell films at the same time;

[0023] c) After the mold cools, it automatically opens and removes the formed male and female shell films.

[0024] Preferably, the cooling temperature control step includes:

[0025] a) Cool the mold using a cooling water system;

[0026] b) Adjust the inlet temperature and flow rate of the cooling water circuit to ensure that the mold temperature is maintained within the set range;

[0027] c) Monitor the mold temperature in real time to avoid deformation of the shell due to overheating or overcooling.

[0028] Preferably, the method further includes the following steps:

[0029] a) Each completed male and female shell membrane shall be uniquely numbered and identified;

[0030] b) Inspect the matching accuracy of the male and female shell membranes to ensure that they meet product quality requirements;

[0031] c) Qualified male and female shell films are directly transferred to the production line for further processing, or temporarily stored in the line-side warehouse for later use;

[0032] d) Record production batch information and establish a product traceability management system.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] By precisely positioning the female and male mold cores, the alignment accuracy of the male and female mold inserts is ensured, significantly reducing mating errors, improving the quality of the contact lens shell, and ensuring better wearing comfort and visual effects. Improved mating accuracy helps reduce defects such as light leakage and air bubbles, ensuring the contact lens's seal and oxygen permeability. The optimized mold structure and precise positioning method reduce manual intervention and adjustment time during production, increasing the automation level of the production line. Male and female shells can be formed in a single mold closure, shortening the production cycle, reducing overall manufacturing costs and production time, and increasing production line capacity. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the upper mold in this invention;

[0036] Figure 2 This is a schematic diagram of the lower mold in this invention.

[0037] in:

[0038] 1. Upper fixing plate; 2. Guide sleeve; 3. Female mold core; 4. Female mold insert; 5. Positioning block; 7. Male mold insert; 8. Female mold pressure block; 9. Injection runner; 10. Cooling water channel; 11. Mold mounting hole; 12. Lower fixing plate; 13. Guide pillar; 14. Top block; 15. Positioning groove; 16. Male mold core. Detailed Implementation

[0039] The invention will now be further described with reference to the accompanying drawings.

[0040] like Figure 1 , Figure 2 As shown, a co-mold injection molding device for male and female contact lens shells includes an upper mold and a lower mold;

[0041] The upper mold includes an upper fixed plate 1, a female mold core 3, and a female mold pressing block 8; the female mold core 3 is placed between the upper fixed plate 1 and the female mold pressing block 8; the female mold pressing block 8 is fixedly connected to the upper fixed plate 1, fixing the female mold core 3 on the upper fixed plate 1; the female mold core 3 is provided with a female mold insert 4 and a male mold insert 7;

[0042] The lower mold includes a lower fixed plate 12, a male mold core 16, and an ejector block 14. The male mold core 16 is positioned between the lower fixed plate 12 and the ejector block 14. The ejector block 14 is fixedly connected to the lower fixed plate 12, fixing the male mold core 16 onto the lower fixed plate 12. The male mold core 16 is provided with male mold inserts 7 and female mold inserts 4 that mate with female mold inserts 4 and male mold inserts 7 on the female mold core 3. Injection runners 9 are provided on both the female mold pressure block 8 and the ejector block 14. Cooling water channels 10 are provided in both the upper fixed plate 1 and the lower fixed plate 12. Mold mounting holes 11 are provided on both the upper fixed plate 1 and the lower fixed plate 12. A 0° positioning block 5 is provided on the female mold core 3, and a 0° positioning groove 15 that mates with the 0° positioning block 5 is provided on the male mold core 16. A guide sleeve 2 is provided on the female mold core 3; a guide post 13 that matches the guide sleeve 2 is fixedly provided on the male mold core 16.

[0043] A method for producing male and female contact lens shells using a co-mold injection molding apparatus includes the following steps:

[0044] The female mold core 3 is fixed on the upper fixing plate 1 by the female mold pressure block 8;

[0045] The male mold core 16 is fixed to the lower fixing plate 12 by the top block 14;

[0046] The male mold plate and the female mold plate are precisely installed and matched through the guide sleeve and guide post 13, and the male mold core 16 and the female mold core 3 are precisely positioned through the 0° positioning block 5 and the 0° positioning groove 15;

[0047] Start the injection molding process on the injection molding machine to produce male and female shell films simultaneously;

[0048] Cooling and temperature control are achieved through an internal water system in the mold;

[0049] Remove the completed male and female shell membranes and transfer them to the next process.

[0050] The injection molding process includes the following steps:

[0051] The temperature, pressure, injection speed, and cooling time of the injection molding machine are set according to the material of the contact lens shell / film.

[0052] After the mold is closed, the molten material is injected into the mold cavity through the injection molding machine, forming male and female shell films at the same time;

[0053] After the mold cools, it automatically opens and removes the formed male and female shell films;

[0054] The cooling and temperature control steps include:

[0055] The mold is cooled by cooling water channel 10;

[0056] Adjust the inlet water temperature and flow rate of cooling water circuit 10 to ensure that the mold temperature is maintained within the set range;

[0057] Monitor the mold temperature in real time to avoid deformation of the shell due to overheating or overcooling;

[0058] Also includes:

[0059] Each completed male and female shell membrane is uniquely numbered and identified;

[0060] Inspect the matching accuracy of the male and female shell membranes to ensure they meet product quality requirements;

[0061] Qualified male and female shell films are directly transferred to the production line for further processing, or temporarily stored in the line-side warehouse for later use.

[0062] Record production batch information and establish a product traceability management system.

[0063] Implementation method 1:

[0064] Injection molding method for male and female contact lens shells – integrated production method:

[0065] Set the injection molding machine temperature, injection pressure, injection speed, and cooling time to ensure that the material melts fully and flows smoothly.

[0066] After the mold is closed, the molten material is injected between the female mold core 3 and the male mold core 16 through the injection channel 9 to form the male and female shell films of the contact lens.

[0067] Cooling is achieved through the cooling water system 10 to ensure stable temperature of the mold and shell, preventing deformation.

[0068] After the mold cools, it automatically opens and the formed male and female shells are extracted.

[0069] Number the finished products, check the matching accuracy, and ensure that the quality meets the standards.

[0070] Qualified male and female shell films are directly transferred to the production line for further processing, or stored in the online side warehouse for later use.

[0071] Record production batch information and establish a product traceability management system.

[0072] Implementation Method 2:

[0073] Injection Molding Method for Male and Female Contact Lens Shells – Staged Production Method:

[0074] First, the female mold core 3 is formed: the injection molding machine is set with appropriate temperature and pressure to close the mold in the area of ​​the female mold core 3 and inject the female mold insert 4 and the male mold insert 7.

[0075] Then remove the female mold core 3 and clean the mold surface, repeating similar steps to form the male mold core 16.

[0076] The female mold core 3 and the male mold core 16 are precisely fitted together, the mold is closed again, and the male and female shell films are formed using the injection runner 9.

[0077] During the mold cooling process, the temperature is controlled through the cooling water system 10 to ensure the stability of the shell and membrane dimensions and prevent deformation.

[0078] After completing the male and female shells, a numbering and matching accuracy check is performed to ensure that the product quality meets the standards.

[0079] Qualified male and female shell membranes are directly transferred to the production line for further processing or storage.

[0080] Record relevant information for each production batch to achieve product traceability management.

[0081] These two implementation methods offer different production strategies, suitable for single-stage or multi-stage processes respectively, to ensure efficient and precise manufacturing of male and female contact lens shells.

Claims

1. A contact lens male and female shell film co-molding injection molding device, comprising an upper mold and a lower mold, wherein the upper mold and the lower mold are combined to form a plurality of molding cavities, the molding cavities comprising two sets of specifications, and the plurality of molding cavities are arranged in a regular manner; The upper mold includes an upper fixed plate (1), a female mold core (3), and a female mold pressing block (8); the female mold core (3) is placed between the upper fixed plate (1) and the female mold pressing block (8); the female mold pressing block (8) is fixedly connected to the upper fixed plate (1) to fix the female mold core (3) on the upper fixed plate (1); the female mold core (3) is provided with a female mold insert (4) and a male mold insert (7); The lower mold includes a lower fixed plate (12), a male mold core (16), and an ejector block (14); the male mold core (16) is placed between the lower fixed plate (12) and the ejector block (14); the ejector block (14) is fixedly connected to the lower fixed plate (12) to fix the male mold core (16) on the lower fixed plate (12); the male mold core (16) is provided with male mold insert (7) and female mold insert (4) that cooperate with female mold insert (4) and male mold insert (7) on the female mold core (3); the female mold pressure block (8) and the ejector block (14) are both provided with injection runners (9); The female mold insert (4) and male mold insert (7) on the female mold core (3) and the male mold insert (7) and female mold insert (4) on the male mold core (16) are combined to form two sets of molded cavities, which are distributed at intervals.

2. The contact lens male and female shell film co-molding injection molding device as described in claim 1, characterized in that, Cooling water channels (10) are provided in both the upper fixing plate (1) and the lower fixing plate (12).

3. The contact lens male and female shell film co-molding injection molding device as described in claim 1, characterized in that, Both the upper fixing plate (1) and the lower fixing plate (12) are provided with code hole (11).

4. The contact lens male and female shell co-molding injection molding device as described in claim 1, characterized in that, The female mold core (3) is provided with a 0° positioning block (5), and the male mold core (16) is provided with a 0° positioning groove (15) that cooperates with the 0° positioning block (5).

5. The contact lens male and female shell co-molding injection molding device as described in claim 1, characterized in that, The female mold core (3) is provided with a guide sleeve (2); the male mold core (16) is fixedly provided with a guide post (13) that is compatible with the guide sleeve (2).

6. The method for producing male and female contact lens shells using a co-mold injection molding apparatus as described in claim 1, characterized in that, Includes the following steps: a) The female mold core (3) is fixed on the upper fixing plate (1) by means of the female mold pressing block (8); b) Fix the male mold core (16) onto the lower fixing plate (12) by means of the top block (14); c) The male mold plate and the female mold plate are precisely installed and matched through the guide sleeve and guide post (13), and the male mold core (16) and the female mold core (3) are precisely positioned through the 0° positioning block (5) and the 0° positioning groove (15); d) Start the injection molding process on the injection molding machine to simultaneously produce male and female shell films; e) Cooling and temperature control are achieved through an internal water system in the mold; f) Remove the completed male and female shell membranes and transfer them to the next process.

7. The method for producing male and female contact lens shells using a co-mold injection molding apparatus as described in claim 6, characterized in that, The injection molding process includes the following steps: a) Set the temperature, pressure, injection speed, and cooling time of the injection molding machine according to the material of the contact lens shell; b) After the mold is closed, the molten material is injected into the mold cavity through the injection molding machine, forming male and female shell films at the same time; c) After the mold cools, it automatically opens and removes the formed male and female shell films.

8. The method for producing male and female contact lens shells using a co-mold injection molding apparatus as described in claim 7, characterized in that, The cooling and temperature control steps include: a) The mold is cooled by the cooling water channel (10); b) Adjust the inlet temperature and flow rate of the cooling water circuit (10) to ensure that the mold temperature is maintained within the set range; c) Monitor the mold temperature in real time to avoid deformation of the shell due to overheating or overcooling.

9. The method for producing male and female contact lens shells using a co-mold injection molding apparatus as described in claim 8, characterized in that, It also includes the following steps: a) Each completed male and female shell membrane shall be uniquely numbered and identified; b) Inspect the matching accuracy of the male and female shell membranes to ensure that they meet product quality requirements; c) Qualified male and female shell films are directly transferred to the production line for further processing, or temporarily stored in the line-side warehouse for later use; d) Record production batch information and establish a product traceability management system.

Images