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CN-121973378-A - Contact lens forming die

CN121973378ACN 121973378 ACN121973378 ACN 121973378ACN-121973378-A

Abstract

The invention discloses a contact lens forming die, and relates to the technical field of contact lens production and manufacturing. The die comprises an upper die assembly and a lower die assembly which are matched with each other, wherein elastic buffer layers are arranged in the upper die assembly and the lower die assembly, and a flash retreating groove assembly is further arranged in the lower die assembly. The invention effectively absorbs the rigid impact force at the moment of die assembly by arranging the elastic gaskets between the upper die core, the lower die core and the die plate as the elastic buffer layer, avoids micro deformation of the die core caused by overlarge stress, thereby ensuring the molding precision of the optical surface of the lens, and simultaneously, can automatically eject the flash solidified in the flash tank during die opening by arranging the flash tank withdrawal assembly consisting of the sliding plate, the spring, the support column and the material sealing ring, thereby realizing the rapid separation of the flash and the die. The invention solves the problems of easy mold core deformation and difficult flash demolding caused by mold closing impact in the prior art, and has the beneficial effects of protecting the precision of the mold core and improving the yield and the production efficiency of products.

Inventors

  • TANG YUXI
  • ZHANG DEBO
  • Cui Huanrui

Assignees

  • 白银鼎好精密注塑有限公司

Dates

Publication Date
20260505
Application Date
20260331

Claims (10)

  1. 1. A contact lens forming die is characterized by comprising an upper die assembly (1) and a lower die assembly (2) which are matched with each other, wherein elastic buffer layers (3) are arranged in the upper die assembly (1) and the lower die assembly (2), and a flash material withdrawal assembly (4) is further arranged in the lower die assembly (2).
  2. 2. The contact lens forming mold according to claim 1, wherein the upper mold assembly (1) comprises an upper mold plate (11) and an upper mold core (12), the upper mold core (12) is adhered to the bottom end of the upper mold plate (11) through an upper elastic gasket (31), and a convex spherical optical surface is arranged at the bottom end of the upper mold core (12).
  3. 3. The contact lens molding die according to claim 2, wherein a boss (13) is provided on a side peripheral wall of the upper mold plate (11).
  4. 4. A contact lens forming mold according to claim 3, wherein the upper mold core (12) has an upper abutment ring (14) provided at an edge thereof.
  5. 5. The contact lens forming mold according to claim 4, wherein the lower mold assembly (2) comprises a lower mold plate (21) and a lower mold core (22), the lower mold core (22) is adhered to the lower mold plate (21) through a lower elastic gasket (32), and a concave spherical optical surface matched with the convex spherical optical surface is arranged at the top end of the lower mold core (22).
  6. 6. The contact lens forming mold according to claim 5, wherein the lower mold plate (21) comprises an outer cylinder (211) and a bearing table (212), the bearing table (212) is integrally formed inside the outer cylinder (211), the lower elastic gasket (32) is adhered to the bearing table (212), and a material overflow groove (213) is formed between the outer cylinder (211) and the bearing table (212).
  7. 7. The contact lens molding die as claimed in claim 6, wherein a lower abutment ring (221) is provided at the edge of the lower mold insert (22), and the upper abutment ring (14) abuts against the lower abutment ring (221) after mold clamping.
  8. 8. The contact lens molding die as claimed in claim 6, wherein the inner peripheral wall of the outer cylinder (211) is provided with a groove (214) adapted to the boss (13).
  9. 9. The contact lens forming mold according to claim 6, wherein the flash withdrawal assembly (4) comprises a sliding plate (41), a spring (42), a support column (43) and a sealing ring (44), the sliding plate (41) is slidably connected inside the outer cylinder (211) and is located below the bearing table (212), the spring (42) is abutted between the sliding plate (41) and the bearing table (212), the sealing ring (44) is slidably arranged in the flash withdrawal groove (213), one end of the support column (43) is connected to the sliding plate (41), and the other end of the support column (43) penetrates through a reserved hole in the lower template (21) and is connected with the sealing ring (44).
  10. 10. The contact lens molding die as claimed in claim 9, wherein a stopper ring (215) for stopping the slide plate (41) is provided at the bottom end of the outer cylinder (211).

Description

Contact lens forming die Technical Field The invention relates to the technical field of contact lens production and manufacturing, in particular to a contact lens forming die. Background Currently, molding (casting) is one of the main processes for producing contact lenses. The technology utilizes a precise metal mold to manufacture a male mold and a female mold, and molds are closed and solidified after liquid monomer is injected. In actual production, in order to ensure the tightness and position accuracy of mold clamping, a rigid hard mold clamping method is generally adopted. However, as shown in the publication CN216860464U, the conventional mold is provided with a thickness stop to prevent deformation of the cutting position, but the rigid impact force is still large at the moment of mold closing. The impact force easily causes tiny deformation of the precise die core, so that the problems of curvature deviation, uneven center thickness, poor edge cutting and the like of the optical surface of the lens are caused, and the optical quality and the yield of the lens are affected. In addition, the flash groove of current mould is mostly fixed knot constructs, and the flash after the solidification is adhesion easily, leads to the drawing of patterns difficulty, has influenced production efficiency. Disclosure of Invention The invention aims to provide a contact lens forming die, which solves the problems that die core deformation is easy to cause by die closing impact and flash demolding is difficult in the background art. In order to achieve the above purpose, the present invention provides the following technical solutions: The utility model provides a contact lens forming die, includes mould subassembly and lower mould subassembly on mutually supporting, all be provided with the elastic buffer layer in last mould subassembly and the lower mould subassembly, still be provided with the flash in the lower mould subassembly and move back the groove subassembly. Optionally, the upper die assembly comprises an upper die plate and an upper die core, the upper die core is adhered to the bottom end of the upper die plate through an upper elastic gasket, and a convex spherical optical surface is arranged at the bottom end of the upper die core. Optionally, a boss is arranged on a side peripheral wall of the upper template. Optionally, an upper abutting ring is arranged at the edge of the upper die core. Optionally, the lower die assembly includes lower bolster and lower mould benevolence, the lower mould benevolence is pasted through lower elastic gasket on the lower bolster, the top of lower mould benevolence be provided with the concave ball optical surface of convex ball optical surface looks adaptation. Optionally, the lower template includes urceolus and plummer, plummer coaxial integrated into one piece is in the urceolus is inside, lower elastic gasket pastes on the plummer, the urceolus with the overflow groove has been seted up between the plummer. Optionally, a lower abutting ring is arranged at the edge of the lower die core, and the upper abutting ring is abutted with the lower abutting ring after die assembly. Optionally, a groove matched with the boss is formed in the inner peripheral wall of the outer cylinder. Optionally, the flash moves back the groove subassembly and includes slide, spring, support column and seal the material ring, slide sliding connection is in the urceolus is inside and be located the plummer below, the spring butt be in the slide with between the plummer, seal the material ring slip setting is in the flash tank, the one end of support column is connected on the slide, the other end pass preformed hole on the lower bolster with seal the material ring connection. Optionally, a limiting ring for limiting the sliding plate is arranged at the bottom end of the outer cylinder. Compared with the prior art, the invention has the beneficial technical effects that: and the mould core precision is protected by arranging elastic gaskets between the upper mould core and the upper mould plate and between the lower mould core and the lower mould plate, so that the traditional rigid hard mould closing mode is changed. The impact force at the moment of die assembly is absorbed and buffered by the elastic gasket, so that micro-deformation of the die core due to overlarge impact force is avoided, the precision and the surface quality of the optical curved surface of the lens are ensured, and the problem that the die core is easy to deform due to rigid die assembly in the background art is solved. The product yield is improved, the elastic buffer is combined with the thickness stop limit formed by the upper abutting ring and the lower abutting ring, so that the uniformity of the thickness of the lens is ensured, the deformation of a cutting position is avoided, and the edge quality of the lens is improved. The production efficiency is improved, namely the overflow can be automatically ejected