Improved structure of contact lens forming mold
By setting the guide slope and clamping edge at the joint part of the contact lens forming mold, the problem of poor mold joint force is solved, and the burrs are removed through the design of the lower mold, which improves the mold yield and wear comfort.
Patent Information
- Application Number
- CN202421822929.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-07-30
AI Technical Summary
The existing contact lens molds have poor bonding strength and cannot remove burrs during the molding and curing process, resulting in low productivity and uncomfortable wearing.
An improved structure of contact lens molding mold is designed. By setting the guide slope and the clamping edge at the joint parts of the upper mold and the lower mold, the close engagement of the mold is enhanced, and the arc bottom edge and sharp corner are provided on the inner wall of the lower mold, which is used to remove the burrs of contact lenses.
Improves the yield of contact lenses when molding, reduces production costs, and provides greater comfort when worn.
Smart Images
Figure CN222987401U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a mold, in particular to an improved structure of a contact lens forming mold for making contact lenses. Background Art
[0002] Press, contact lenses are mostly manufactured by molds. At present, existing contact lens forming molds all have an upper mold and a lower mold. The upper mold and the lower mold can be joined together (or called mold closing) or separated (or called mold opening). After joining, a forming cavity can be formed between the upper mold and the lower mold. Polymer material is injected into the forming cavity, and then the polymer material in the forming cavity is cured by heating or light irradiation, and the production of the contact lens can be completed after the demolding step of separating the upper and lower molds.
[0003] However, the existing structure as described above still has the following problems in practical applications: (1) Volatile gases will be generated in the forming cavity during the curing process of heating or light irradiation of the polymer material, and the volatile gases will push the upper mold to displace upward. In a structure with poor joining force, the yield of the contact lens during production will be greatly reduced; (2) Burrs will be generated at the edge of the contact lens after curing. If the burrs are not properly removed, the comfort after wearing will be seriously affected.
[0004] Therefore, how to research and improve the above-mentioned disadvantages of the existing structure is actually the goal that the relevant industry needs to strive for. In view of this, the inventor of the utility model had the idea of creation, and then designed it with years of experience. After many discussions, sample tests were made, and after many corrections and improvements, the present utility model was finally launched. Content of the Utility Model
[0005] Technical problems to be solved:
[0006] The joining force of the existing production mold for contact lenses is poor, and burrs cannot be removed during the forming and curing process. This is the technical problem to be solved.
[0007] Technical features for solving the problems:
[0008] The present utility model provides an improved structure for a contact lens forming mold, which includes: an upper mold and a lower mold. Among them, the upper mold has a first bowl portion and an annular wall. The annular wall is located above the first bowl portion, and a first step edge is connected to the outer side of the top end of the annular wall. The first step edge includes a first horizontal portion, a vertical portion, and a second horizontal portion. The first horizontal portion is arranged between the annular wall and the vertical portion, and the second horizontal portion is connected outward through the vertical portion. Moreover, the outer diameter of the vertical portion is arranged in a tapered shape that gradually shrinks from top to bottom, so that the outer wall of the vertical portion can become a guiding inclined surface, and a plurality of ventilation grooves are arranged on the guiding inclined surface. The lower mold has a second bowl portion and a second step edge that are connected. By connecting the second step edge, a set of connecting holes can be formed above the second bowl portion. The hole edges of the set of connecting holes gradually expand from top to bottom, so that a relatively narrowed clamping edge is formed above the set of connecting holes. When the upper mold and the lower mold are engaged, the guiding inclined surface is used to provide guidance, so that the vertical portion of the first step edge can be more easily inserted into the set of connecting holes. By the narrowing of the clamping edge, a pressing force is generated on the guiding inclined surface, so that the upper mold and the lower mold can be more firmly engaged after being joined. Moreover, a first concave surface is arranged on the inner wall of the second bowl portion. The first concave surface has an arc bottom edge, and a sharp corner is bent upward on one side of the arc bottom edge. By using the sharp corner for truncation, the excess burrs on the contact lens can be removed, so that the contact lens can be more comfortable to wear. Thus, an improved structure for a contact lens forming mold is obtained.
[0009] As a further improvement of the present utility model, the outer wall of the first bowl portion is a convex optical surface, and the inner wall of the second bowl portion is a concave optical surface. When the upper mold and the lower mold are engaged, a forming cavity can be formed between the convex optical surface and the concave optical surface.
[0010] As a further improvement of the present utility model, a toothed portion is arranged on the outer periphery of the annular wall, and the bottom edge of the toothed portion is arranged in a slanted shape.
[0011] As a further improvement of the present utility model, the second step edge includes a first horizontal section, a vertical section, and a second horizontal section, so that the set of connecting holes can be arranged inside the vertical section.
[0012] As a further improvement of the present utility model, a second concave surface is further arranged above the first concave surface.
[0013] Efficacy compared with the prior art:
[0014] (1) The present utility model provides an improved structure for a contact lens molding die. By using the clamping edge to tightly press on the inclined guide surface, the upper die and the lower die can be tightly joined together. Therefore, relatively speaking, there is no situation where the upper die is pushed upward by the volatile gas, resulting in deformation of the incompletely cured contact lens and becoming a waste product. The yield rate during molding is high, which can effectively reduce production costs and improve the industrial competitiveness accordingly.
[0015] (2) The present utility model provides an improved structure for a contact lens molding die. The cooperation between the clamping edge and the inclined guide surface is effective, and the structure is simple and not complex. In this way, the mold opening cost can also be effectively reduced.
[0016] (3) The present utility model provides an improved structure for a contact lens molding die. When the upper die and the lower die are joined, they can remove the burrs generated at the edge of the contact lens at the same time. Therefore, there is no need to grind the burrs separately in a subsequent processing step after molding, making the molding of the contact lens simpler, faster, and relatively more comfortable to wear. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 is a three-dimensional combined view of the present utility model.
[0018] Figure 2 is a three-dimensional exploded view of the present utility model.
[0019] Figure 3 is a view showing the joined state of the upper die and the lower die of the present utility model.
[0020] Figure 4 is a view showing the pressing state during joining of the present utility model.
[0021] Figure 5 is a view showing the burr-removing state during joining of the present utility model.
[0022] Figure 6 is a sectional view during the molding of the contact lens of the present utility model.
[0023] Figure 7 is a sectional view from another angle during the molding of the contact lens of the present utility model.
[0024] Figure 8 is a view showing the mold-opening state after the contact lens of the present utility model is molded.
[0025] Symbol Explanation:
[0026] Part of the present utility model:
[0027] Upper die - (10) First bowl part - (11)
[0028] Circular wall - (12) Tooth-shaped part - (121)
[0029] The first edge --- (13) The first horizontal part --- (131)
[0030] The vertical part --- (132) The second horizontal part --- (133)
[0031] The guiding inclined surface --- (134) The air permeable groove --- (135)
[0032] The lower mold --- (20) The second bowl part --- (21)
[0033] The first concave surface --- (211) The arc bottom edge --- (212)
[0034] The sharp corner --- (213) The second concave surface --- (214)
[0035] The second edge --- (22) The connecting hole --- (221)
[0036] The clamping edge --- (222) The first horizontal section --- (223)
[0037] The vertical section --- (224) The second horizontal section --- (225)
[0038] Contact lens --- (30) Polymer material --- (300)
[0039] Flash --- (31) Detailed implementation manners
[0040] To further understand and recognize the purpose, features and effects of the present utility model, the following examples are listed in conjunction with [Brief description of the drawings] and are described in detail as follows:
[0041] First, please start from Figure 1 and Figure 2As shown, it includes an upper mold (10) and a lower mold (20). Among them, the upper mold (10) has a first bowl portion (11) and an annular wall (12). The annular wall (12) is located above the first bowl portion (11). And a first step edge (13) is connected to the outer side of the top end of the annular wall (12). The first step edge (13) includes a first horizontal portion (131), a vertical portion (132), and a second horizontal portion (133). The first horizontal portion (131) is provided between the annular wall (12) and the vertical portion (132). Then, the second horizontal portion (133) is externally connected through the vertical portion (132). Also, the outer diameter of the vertical portion (132) is set to be an inclined cone shape that gradually shrinks from top to bottom, so that the outer wall of the vertical portion (132) can become a guiding inclined surface (134). And a plurality of air vent grooves (135) are provided on the guiding inclined surface (134). The lower mold (20) has a second bowl portion (21) and a second step edge (22) that are connected. By connecting the second step edge (22), a set of connecting holes (221) can be formed above the second bowl portion (21). The hole edges of the set of connecting holes (221) gradually expand from top to bottom, so as to form a relatively narrowed clamping edge (222) above the set of connecting holes (221). When the upper mold (10) and the lower mold (20) are engaged (please also refer to Figure 3 shown), the guiding inclined surface (134) is used to provide guidance, so that the vertical portion (132) of the first step edge (13) can be more easily inserted into the set of connecting holes (221). By the narrowing of the clamping edge (222) to generate a pressing force on the guiding inclined surface (134), the upper mold (10) and the lower mold (20) can be more firmly engaged after being engaged (please also refer to Figure 4 shown). Also, a first concave surface (211) is provided on the inner wall of the second bowl portion (21). The first concave surface (211) has an arc bottom edge (212). A sharp corner (213) is bent upward on one side of the arc bottom edge (212). By using the sharp corner (213) for cutting, the excess burrs (31) on the contact lens (30) can be removed (please also refer to Figure 5 shown), making the contact lens (30) more comfortable to wear.
[0042] The present utility model provides an improved structure of a contact lens molding mold. Among them, the outer wall of the first bowl portion (11) is a convex optical surface, and the inner wall of the second bowl portion (21) is a concave optical surface. When the upper mold (10) and the lower mold (20) are engaged, a molding cavity can be formed between the convex optical surface and the concave optical surface.
[0043] The present utility model provides an improved structure of a contact lens molding mold. Among them, a toothed portion (121) is provided on the outer periphery of the annular wall (12), and the bottom edge of the toothed portion (121) is set to be inclined.
[0044] The present utility model provides an improved structure of a contact lens forming mold. Among them, the second step edge (22) includes a first horizontal section (223), a vertical section (224) and a second horizontal section (225), so that the connecting hole (221) can be arranged inside the vertical section (224).
[0045] The present utility model provides an improved structure of a contact lens forming mold. Among them, a second concave surface (214) is further arranged above the first concave surface (211).
[0046] During actual use, a polymer material (300) is injected into the forming cavity. After injection, the polymer material (300) in the forming cavity is cured by heating or light irradiation, so that the contact lens (30) can be successfully formed in the forming cavity. By pressing the clamping edge (222) against the guiding inclined surface (134), it can prevent the upper mold (10) from being pushed upward due to the volatilized gas generated during the curing of the polymer material (300), so that the upper mold (10) and the lower mold (20) can be firmly maintained in the engaged state (please refer to Figure 6 and Figure 7 shown), so as to greatly improve the yield rate of the contact lens (30) during production. At the same time, the air vent groove (135) can also exhaust air appropriately. Moreover, during the engagement process, the excess burrs (31) formed on the edge of the contact lens (30) can be cut off by the contact between the sharp corner (213) and the first bowl part (11) (please refer to Figure 5 shown), so that the contact lens (30) will not be seriously affected by the excessive roughness of the edge burrs (31) and the comfort during wearing. When the upper mold (10) and the lower mold (20) are separated to complete the demolding step, the contact lens (30) can be successfully taken out (please refer to Figure 8 shown).
[0047] Through the structure of the above specific embodiments, the following benefits can be obtained: (1) By using the card edge (222) to press tightly on the guide inclined surface (134), the upper mold (10) and the lower mold (20) can be tightly joined together. Therefore, relatively speaking, there is no situation where the upper mold (10) is pushed upward by the volatile gas, resulting in the deformation of the incompletely cured contact lens (30) and becoming a waste product. The yield during molding is high, which can effectively reduce the production cost and improve the industrial competitiveness accordingly; (2) The cooperation between the card edge (222) and the guide inclined surface (134) is effective, and the structure is simple and not complex. In this way, the mold opening cost can also be effectively reduced; (3) The upper mold (10) and the lower mold (20) can remove the burrs (31) generated at the edge of the contact lens (30) while being joined. Therefore, there is no need to grind the burrs (31) separately in a post-processing step after molding, making the molding of the contact lens (30) simpler, faster, and relatively more comfortable to wear.
[0048] The above content is only a preferred embodiment of the present invention, and should not be used to limit the scope of implementation of the present invention; that is, all equivalent changes and modifications made according to the scope of the patent application of the present invention should still fall within the scope covered by the patent of the present invention.
Claims
1. An improved structure of a contact lens molding mold, characterized in that: It includes: an upper die and a lower die, wherein: The upper mold has a first bowl portion and an annular wall, the annular wall is located above the first bowl portion, and the top of the annular wall is connected to a first step edge, the first step edge includes a first horizontal portion, a vertical portion and a second horizontal portion, the first horizontal portion is arranged between the annular wall and the vertical portion, and the second horizontal portion is connected to the vertical portion outwardly, and the outer diameter of the vertical portion is arranged in an oblique cone shape that gradually decreases from top to bottom, so that the outer wall of the vertical portion can become a guide slope, and a plurality of air permeable grooves are arranged on the guide slope; The lower mold has a second bowl portion and a second step edge connected to each other. The second step edge can form a group of connection holes above the second bowl portion. The hole edges of the group of connection holes gradually expand from top to bottom to form a relatively narrow card edge above the group of connection holes. When the upper mold is engaged with the lower mold, the guide bevel is used to provide guidance so that the upright portion of the first step edge can be more easily inserted into the group of connection holes. The narrowing of the card edge tightens the guide bevel, so that the upper mold and the lower mold can be more tightly engaged. The inner wall of the second bowl portion is provided with a first concave surface, and the first concave surface has an arc bottom edge. The arc bottom edge has a sharp corner on one side. The sharp corner is used for truncation to remove excess burrs on the contact lens, making the contact lens more comfortable to wear.
2. The improved structure of the contact lens molding mold according to claim 1, characterized in that: The outer wall of the first bowl portion is a convex optical surface, and the inner wall of the second bowl portion is a concave optical surface. When the upper mold and the lower mold are connected, a molding cavity can be formed between the convex optical surface and the concave optical surface.
3. The improved structure of the contact lens molding mold according to claim 1, characterized in that: A toothed portion is arranged on the outer periphery of the annular wall, and the bottom edge of the toothed portion is arranged in an inclined surface shape.
4. The improved structure of the contact lens molding mold according to claim 1, characterized in that: The second step edge includes a first horizontal section, a vertical section and a second horizontal section, so that the assembly hole can be arranged inside the vertical section.
5. The improved structure of the contact lens molding mold according to claim 1, characterized in that: A second concave surface is further provided above the first concave surface.