An optical lens injection mold and its injection method

Abstract

The present invention relates to the technical field, and particularly to an optical lens injection mold and an injection method thereof. An optical lens injection mold includes a core structure, an upper mold structure, and a lower mold structure. The core structure includes an upper core, an inner lower core, and an outer lower core. The upper mold structure includes an upper template, an upper mold base plate, an upper demolding structure, and a sprue bushing. The lower mold structure includes a lower template, a support plate, a lower mold base plate, a first ejecting structure, a second ejecting structure, and a driving mechanism. By changing the demolding method of the optical lens from the core ejection that controls the surface shape to the core ejection that controls the outer diameter, during the entire demolding process, under the action of the upper demolding structure, the first ejecting structure, and the second ejecting structure, only the outer lower core that controls the outer diameter moves relative to the lower template to achieve demolding, which further improves the eccentricity accuracy of the upper and lower optical surfaces of the lens, thereby improving the optical quality of the lens.

Description

Technical Field

[0001] The present invention relates to the technical field of lens manufacturing, and particularly to an optical lens injection mold and an injection method thereof. Background Art

[0002] With the rapid iteration of mobile phone consumer electronic products, consumers are paying more and more attention to the quality and functions of products. This includes the field of mobile phone lenses. Stimulated by the upgrading of consumer demands, high-quality lenses with various functions have emerged in the field of mobile phone lenses: telephoto lenses, macro lenses, wide-angle lenses, fish-eye lenses, portrait lenses, etc. Such market demands determine that future lens production will impose higher requirements on lens manufacturers. For example, the assembly accuracy of lenses, the imaging quality of lenses, and so on.

[0003] However, along with the increase in lens classification and the continuous improvement of product quality requirements, the technical level of traditional production has reached a bottleneck and cannot make corresponding progress. As a result, when producing new high-end lenses, production can only be carried out by sacrificing the product yield rate, which not only causes huge waste of resources but also hinders the further research and mass production of many new products.

[0004] Currently, the mature processes for lens production mainly include direct injection molding and molding pressing, and direct injection molding is the molding method with the largest proportion. There have always been two problems that trouble producers during the direct injection molding production process - the service life of the male mold core, the eccentricity of lens molding, and the surface quality. The reason for these problems is that during the injection molding production process, in order to ensure the surface shape and imaging quality of the lens, the male mold core requires a smaller design tolerance gap with the mold cavity it makes. However, when the design tolerance gap is very small, the actuation and lubrication quality of the male mold core will seriously decline.

[0005] The mold core secondary ejection technology can solve these problems to a certain extent, and the molding quality of the optical zone of the product will also be further improved. However, at present, each lens production enterprise does not have a complete and mature mold design and actuation scheme for mold core secondary ejection. Especially in the field of lens blank production, there is no mature design scheme and successful production practice for such a technical route.

[0006] Therefore, it is particularly urgent to design a new injection molding scheme that can overcome the current bottleneck of lens injection molding technology. Summary of the Invention

[0007] The purpose of the present invention is to at least solve one of the technical problems existing in the prior art, and to provide an optical lens injection mold and an injection method thereof.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows: An optical lens injection mold includes a core structure, an upper mold structure, and a lower mold structure.

[0009] The core structure includes an upper core, an inner lower core, and an outer lower core. The upper core, the inner lower core, and the outer lower core respectively form the upper surface, the lower surface, and the side surface of the lens.

[0010] The upper mold structure includes an upper template, an upper mold base plate, an upper demolding structure, and a sprue bushing. The upper template is fixedly connected to the upper mold base plate. The upper core and the sprue bushing are fixedly arranged in the upper template. A ejector part connected to the lens is formed between the sprue bushing and the core structure. The upper demolding structure is used to resist the lens and the ejector part during demolding, so that the upper core is separated from the upper surface of the lens, and the sprue bushing is separated from the ejector part.

[0011] The lower mold structure includes a lower template, a support plate, a lower mold base plate, a first ejecting structure, a second ejecting structure, and a driving mechanism. The lower template is arranged on the support plate, and the support plate is fixed on the lower mold base plate. The outer lower core is fixed on the first ejecting structure, the inner lower core is fixed on the support plate, and the driving mechanism is used to drive the first ejecting structure to act to drive the outer lower core to move upward relative to the inner lower core, so that the lower surface of the lens is separated from the inner lower core. The second ejecting structure is arranged below the ejector part, and the driving mechanism is used to drive the second ejecting structure to act to drive the ejector part to move upward, so that the side surface of the lens is separated from the outer lower core.

[0012] Further, the upper demolding structure includes an upper mold insert. A first elastic member is arranged between the top of the upper mold insert and the upper template and connected through the first elastic member, and the bottom abuts against the ejector part.

[0013] Further, the upper demolding structure includes a first limiting member. One end of the first limiting member is connected to the upper template, and the other end is clamped with the upper mold insert to limit the moving distance of the upper mold insert.

[0014] Further, the first ejecting structure includes a first ejecting plate and a first ejecting rod, and the second ejecting structure includes a second ejecting plate and a second ejecting rod. The first ejecting plate and the second ejecting plate are arranged on the lower mold base plate so as to be movable up and down. The second ejecting plate abuts on the upper surface of the first ejecting plate. The first ejecting rod is fixed on the first ejecting plate, and the second ejecting rod is fixed on the second ejecting plate.

[0015] Further, the first ejecting rod is connected to the outer lower core, and the second ejecting rod abuts against the ejector part.

[0016] Further, the driving mechanism includes a first pushing rod, a slider, a first limiting block, and a second limiting block. The first pushing rod passes through the first ejector plate and abuts against the second ejector plate. The front and rear ends of the slider are respectively clamped with the first ejector plate. The left side of the slider is meshed and connected with the first pushing rod. The upper and lower end faces of the slider are inclined upward to the upper right. The top of the first limiting block is fixed on the support plate, and the bottom abuts against the upper end face of the slider. The bottom of the second limiting block is fixed on the lower die base plate, and the top abuts against the lower end face of the slider. A chute for the slider to move upward to the upper right is formed between the first limiting block and the second limiting block.

[0017] Further, the driving mechanism includes a second pushing rod, an elastic opening and closing structure, and a second limiting member. The elastic opening and closing structure is arranged on the first ejector plate. The second pushing rod is used to push the elastic opening and closing structure and the first ejector plate to move upward. One end of the second limiting member is connected to the lower die base plate, and the other end is clamped with the first ejector plate to limit the moving distance of the first ejector plate. When the first ejector plate reaches the maximum moving distance, the second pushing rod pushes the elastic opening and closing structure to open and continues to move upward to act on the second ejector plate to push the second ejector plate to move upward.

[0018] Further, the elastic opening and closing structure includes two elastic sliders arranged opposite to each other left and right. Compression springs are respectively connected to the left and right sides of the two elastic sliders. A bayonet cooperating with the second pushing rod is arranged between the two elastic sliders.

[0019] Further, the driving mechanism includes a third pushing rod and a lever. The third pushing rod is used to push the first ejector plate to move upward. The lever includes a long side, a short side, and a node where the long side and the short side intersect. The node of the lever is rotatably arranged on the first ejector plate. The end point of the short side abuts against the support plate, and the end point of the long side abuts against the second ejector plate.

[0020] Further, the driving mechanism includes a fourth pushing rod, a first upper compression spring, a first lower compression spring, and a third limiting member. The fourth pushing rod is used to push the second ejector plate to move upward. The top of the first upper compression spring is connected to the support plate, and the bottom is connected to the second ejector plate. The top of the first lower compression spring is connected to the first ejector plate, and the bottom is connected to the lower die base plate. One end of the third limiting member is connected to the lower die base plate, and the other end is clamped with the first ejector plate to limit the moving distance of the first ejector plate.

[0021] Further, the driving mechanism includes a pull rod, a second upper compression spring, a second lower compression spring, and a fourth limiting member. The top of the pull rod is connected to the second upper compression spring, and the bottom abuts against the first ejector plate and is clamped with the second ejector plate. The top of the second upper compression spring is connected to the upper die base plate, and the bottom is connected to the pull rod. The top of the second lower compression spring is connected to the first ejector plate, and the bottom is connected to the lower die base plate. One end of the fourth limiting member is connected to the lower die base plate, and the other end is clamped with the first ejector plate to limit the moving distance of the first ejector plate.

[0022] The present invention also provides an injection molding method for an optical lens injection mold, including the following steps:

[0023] Step 1, injecting through the sprue bushing into the mold core structure, so that the lens is formed in the mold core structure, and the ejector part is formed between the sprue bushing and the mold core structure;

[0024] Step 2, the upper template moves upward to separate from the lower template, the upper demolding structure abuts against the lens and the ejector part, and the upper mold core moves upward following the upper template, so that the upper surface of the upper mold core is separated from the lens, and the sprue bushing is separated from the ejector part;

[0025] Step 3, the upper template continues to move upward to a certain position, and the driving mechanism drives the first ejecting structure to act to drive the outer lower mold core to move upward relative to the inner lower mold core, so that the lower surface of the lens is separated from the inner lower mold core;

[0026] Step 4, the driving mechanism drives the second ejecting structure to act to drive the ejector part to move upward, so that the side surface of the lens is separated from the outer lower mold core, and demolding is completed to remove the lens.

[0027] As can be seen from the above description of the present invention, compared with the prior art, the optical lens injection mold of the present invention has at least one of the following beneficial effects:

[0028] 1. By changing the demolding method of the optical lens from the ejection of the mold core controlling the surface shape to the ejection of the mold core controlling the outer diameter, during the entire demolding process, under the action of the upper demolding structure, the first ejecting structure, and the second ejecting structure, the upper mold core controlling the surface shape of the lens moves following the upper template, the inner lower mold core controlling the surface shape of the lens is fixed on the support plate without moving, the outer lower mold core controlling the outer diameter of the lens moves following the first ejecting structure, and the upper mold core and the inner lower mold core do not move relative to the upper template and the lower template respectively, avoiding manufacturing errors caused by the movement of the mold core controlling the surface shape. Only the outer lower mold core controlling the outer diameter moves relative to the lower template to achieve demolding, further improving the eccentricity accuracy of the upper and lower optical surfaces of the lens, thereby improving the optical quality of the lens.

[0029] 2. When the surface shape of the lens is relatively complex, resulting in the demolding force of the surface shape being greater than that of the outer diameter, whether it is an integral demolding or a demolding method using a mold core ejection, due to the large demolding force of the surface shape, it will cause damage to the structure of the lens. By using the demolding method of the optical lens injection mold of the present invention, first, the surface shape area with a large demolding force is removed through the overall uniform ejection action of the outer lower mold core, and then the outer diameter area with a small demolding force is removed, which can make the force on each part of the lens more balanced during the demolding process and can greatly reduce the demolding damage of the aspherical lens with a large demolding force during the demolding process.

[0030] 3. The optical lens injection mold of the present invention can especially greatly improve the accuracy of the lens with the positioning structure arranged inside. Since the positioning structure of the lens is arranged inside and does not use the outer edge for positioning, the requirement for the outer diameter size is relatively low. By setting the ejection mechanism in the part that only affects the outer diameter, the positioning accuracy of the positioning structure can be greatly improved, effectively improving the assembly stability of the lens and improving the optical performance of the lens.

[0031] 4. The optical lens injection mold of the present invention has a multi-stage ejection, which solves the problem of mold core ejection jamming. Since the lens surface contains steps or the surface shape is relatively tortuous, by using multi-stage ejection, during the demolding process, the overall adhesion force of the mold to the lens is dispersed, thus avoiding the phenomenon of poor demolding on the lens surface, reducing the force of the mold on the lens, and making the lens not easily deformed.

[0032] 5. The multi-stage mold release method used in the optical lens injection mold of the present invention increases the number of inserts in the cavity. The gaps between the inserts are beneficial to the exhaust function during the molding process, effectively improving the problem of trapped air and other phenomena during the lens molding.

[0033] 6. During the entire demolding process of the injection molding method of the present invention, the upper mold core and the inner lower mold core that control the lens surface shape do not move relative to the upper template and the lower template respectively, avoiding manufacturing errors caused by the movement of the mold core that controls the surface shape. Only by making the outer lower mold core that controls the outer diameter move relative to the lower template can demolding be achieved, improving the optical quality of the lens. Description of the Drawings

[0034] Figure 1 It is one of the structural schematic diagrams of an optical lens injection mold in the first specific embodiment of the present invention;

[0035] Figure 2 It is Figure 1 The enlarged view of part A;

[0036] Figure 3 It is Figure 1 The enlarged view of part B;

[0037] Figure 4 It is the cross-sectional schematic diagram of the slider and the first ejection plate in the preferred embodiment of the present invention;

[0038] Figure 5 It is a partial structural schematic diagram of the lens in the preferred embodiment of the present invention;

[0039] Figure 6 It is the second structural schematic diagram of an optical lens injection mold in the first specific embodiment of the present invention;

[0040] Figure 7 It is the third structural schematic diagram of an optical lens injection mold in the first specific embodiment of the present invention;

[0041] Figure 8 It is the fourth structural schematic diagram of an optical lens injection mold in the first specific embodiment of the present invention;

[0042] Figure 9 It is the fifth structural schematic diagram of an optical lens injection mold in the first specific embodiment of the present invention;

[0043] Figure 10 It is the structural schematic diagram of an optical lens injection mold in the second specific embodiment of the present invention;

[0044] Figure 11 It is the structural schematic diagram of an optical lens injection mold in the third specific embodiment of the present invention;

[0045] Figure 12 It is the structural schematic diagram of an optical lens injection mold in the fourth specific embodiment of the present invention;

[0046] Figure 13 It is the structural schematic diagram of an optical lens injection mold in the fifth specific embodiment of the present invention;

[0047] Reference numerals: 1, core structure; 2, upper die structure; 3, lower die structure; 4, lens; 5, ejector part; 11, upper core; 12, inner lower core; 13, outer lower core; 21, upper template; 22, upper die seat plate; 23, upper demolding structure; 24, sprue bushing; 31, lower template; 32, support plate; 33, lower die seat plate; 34, first ejecting structure; 35, second ejecting structure; 36, driving mechanism; 231, upper insert block; 232, first elastic member; 233, first limiting member; 341, first ejecting plate; 342, first ejecting rod; 351, second ejecting plate; 352, second ejecting rod; 361a, first pusher rod; 362a, slider; 363a, first limiting block; 364a, second limiting block; 361b, second pusher rod; 362b, elastic opening and closing structure; 363b, second limiting member; 361c, third pusher rod; 362c, lever; 361d, fourth pusher rod; 362d, first upper compression spring; 363d, first lower compression spring; 364d, third limiting member; 361e, pull rod; 362e, second upper compression spring; 363e, second lower compression spring; 364e, fourth limiting member. Detailed implementation mode

[0048] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0049] Those skilled in the art should understand that in the disclosure of the present invention, the orientation or positional relationships indicated by the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting the present invention.

[0050] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations. Specific embodiment 1:

[0052] Refer to Figure 1-9As shown in the figure, a preferred embodiment of the present invention is an optical lens injection mold, which includes a core structure 1, an upper mold structure 2, and a lower mold structure 3.

[0053] The core structure 1 includes an upper core 11, an inner lower core 12, and an outer lower core 13. The upper core 11, the inner lower core 12, and the outer lower core 13 respectively form the upper surface, the lower surface, and the side surface of the lens 4.

[0054] The upper mold structure 2 includes an upper template 21, an upper mold base plate 22, an upper demolding structure 23, and a sprue bushing 24. The upper template 21 is fixedly connected to the upper mold base plate 22. The upper core 11 and the sprue bushing 24 are fixedly arranged in the upper template 21. A ejector part 5 connected to the lens 4 is formed between the sprue bushing 24 and the core structure 1. The upper demolding structure 23 is used to resist the lens 4 and the ejector part 5 during demolding, so that the upper core 11 is separated from the upper surface of the lens 4, and the sprue bushing 24 is separated from the ejector part 5.

[0055] The lower mold structure 3 includes a lower template 31, a support plate 32, a lower mold base plate 33, a first ejecting structure 34, a second ejecting structure 35, and a driving mechanism 36. The lower template 31 is arranged on the support plate 32. The support plate 32 is fixed on the lower mold base plate 33. The outer lower core 13 is fixed on the first ejecting structure 34. The inner lower core 12 is fixed on the support plate 32. The driving mechanism 36 is used to drive the first ejecting structure 34 to act to drive the outer lower core 13 to move upward relative to the inner lower core 12, so that the lower surface of the lens 4 is separated from the inner lower core 12. The second ejecting structure 35 is arranged below the ejector part 5. The driving mechanism 36 is used to drive the second ejecting structure 35 to act to drive the ejector part 5 to move upward, so that the side surface of the lens 4 is separated from the outer lower core 13.

[0056] In the optical lens injection mold of the present invention, the demolding method of the optical lens 4 is changed from the core ejection of controlling the surface shape to the core ejection of controlling the outer diameter. During the entire demolding process, under the action of the upper demolding structure 23, the first ejecting structure 34, and the second ejecting structure 35, the upper core 11 controlling the surface shape of the lens 4 moves with the upper template 21, the inner lower core 12 controlling the surface shape of the lens 4 is fixed on the support plate 32 and does not move, the outer lower core 13 controlling the outer diameter of the lens 4 moves with the first ejecting structure 34, and the upper core 11 and the inner lower core 12 do not move relative to the upper template 21 and the lower template 31 respectively, avoiding manufacturing errors caused by the movement of the core for controlling the surface shape. Only by moving the outer lower core 13 for controlling the outer diameter relative to the lower template 31 can demolding be achieved, further improving the eccentricity accuracy of the upper and lower optical surfaces of the lens 4, thereby improving the optical quality of the lens 4.

[0057] Refer to Figure 5As shown, when the surface shape of the lens 4 is relatively complex, resulting in the demolding force of the surface shape being greater than that of the outer diameter, whether it is integral demolding or the demolding method using a mold core pulling, due to the large demolding force of the surface shape, damage to the structure of the lens 4 will occur; while using the demolding structure of the optical lens injection mold of the present invention, first, the surface shape area with a large demolding force is removed by the overall uniform ejection action of the outer lower mold core 13, and then the outer diameter area with a small demolding force is removed, which can make the force on each part of the lens 4 more balanced during the demolding process, and can greatly reduce the demolding damage of the aspherical lens 4 with a large demolding force during the demolding process.

[0058] The optical lens injection mold of the present invention can particularly improve the accuracy of the lens 4 with the positioning structure arranged inside. Since the positioning structure of the lens 4 is arranged inside and does not use the outer edge for positioning, the requirements for the outer diameter size are relatively low. By arranging the ejection mechanism in the part that only affects the outer diameter, the positioning accuracy of the positioning structure can be greatly improved, effectively improving the assembly stability of the lens 4 and improving the optical performance of the lens.

[0059] The optical lens injection mold of the present invention has a multi-stage ejection, which solves the problem of mold core ejection jamming. Since the surface of the lens 4 contains steps or the surface shape is relatively tortuous, using multi-stage ejection, during the demolding process, the overall adhesion force of the mold to the lens 4 is dispersed, thus avoiding the phenomenon of poor demolding on the surface of the lens 4, reducing the force of the mold on the lens 4, and making the lens 4 not easily deformed.

[0060] The multi-stage mold release method used in the optical lens injection mold of the present invention increases the number of inserts in the cavity. The gaps between the inserts are beneficial to the exhaust function during the molding process, effectively improving the problems such as air entrapment during the molding of the lens 4.

[0061] As a preferred embodiment of the present invention, it may further have the following additional technical features:

[0062] In this embodiment, the upper demolding structure 23 includes an upper mold insert 231. A first elastic member 232 is arranged between the top of the upper mold insert 231 and the upper template 21 and is connected through the first elastic member 232. The bottom is in contact with the ejection part 5. The upper demolding structure 23 includes a first limiting member 233. One end of the first limiting member 233 is connected to the upper template 21, and the other end is clamped with the upper mold insert 231 to limit the movement distance of the upper mold insert 231.

[0063] Refer to Figure 6As shown, when the mold starts to demold, at the first-stage position, the upper template 21 and the lower template 31 begin to separate. The upper die insert 231 is ejected by the first elastic member 232 by a distance d1. Under the action of the first limiting member 233, the upper die insert 231 stops after moving a distance d1. During the ejection process of the upper die insert 231, the ejected part 5 and the lens 4 are separated from the sprue bushing 24 and the upper die core 11, completing the first-step demolding action.

[0064] Figure 7 As shown Figure 6 At the second-stage position after the further separation of the shown mold, the upper template 21 and the lower template 31 are further separated by a distance d2. The upper die insert 231 is separated from the lower template 31 under the action of the first limiting member 233, completing the second-step demolding action.

[0065] In this embodiment, the first ejection structure 34 includes a first ejection plate 341 and a first ejection rod 342. The second ejection structure 35 includes a second ejection plate 351 and a second ejection rod 352. The first ejection plate 341 and the second ejection plate 351 are movably arranged up and down on the lower die base plate 33. The second ejection plate 351 abuts on the upper surface of the first ejection plate 341. The first ejection rod 342 is fixed on the first ejection plate 341. The second ejection rod 352 is fixed on the second ejection plate 351. The first ejection rod 342 is connected to the outer lower die core 13. The second ejection rod 352 abuts on the ejected part 5.

[0066] In this embodiment, the driving mechanism 36 includes a first pushing rod 361a, a slider 362a, a first limiting block 363a, and a second limiting block 364a. The first pushing rod 361a passes through the first ejection plate 341 and abuts on the second ejection plate 351. The front and rear ends of the slider 362a are respectively clamped with the first ejection plate 341. The left side of the slider 362a is meshed and connected with the first pushing rod 361a. The upper and lower end faces of the slider 362a are inclined upward to the right. The top of the first limiting block 363a is fixed on the support plate 32, and the bottom abuts on the upper end face of the slider 362a. The bottom of the second limiting block 364a is fixed on the lower die base plate 33, and the top abuts on the lower end face of the slider 362a. A chute for the slider 362a to move upward and to the right is formed between the first limiting block 363a and the second limiting block 364a.

[0067] Figure 8 As shown Figure 7After the shown mold continues to separate, the first ejector rod 361a starts to push upward under the control of the injection molding machine. At this time, under the pushing distance d3 of the first ejector rod 361a, the slider 362a drives the first ejector plate 341, and the first ejector rod 361a pushes the second ejector plate 351 to move synchronously by a distance d3. Then, under the pushing of the first ejector plate 341 and the second ejector plate 351, the first ejector rod 342, the second ejector rod 352 and the outer lower die core 13 push the lens 4 and the ejecting part 5 to eject upward by a distance d3, so that the lens 4 is separated from the lower template 31 and the inner lower die core 12, completing the third demolding action.

[0068] Figure 9 shown Figure 8 After the shown mold continues to separate, the first ejector rod 361a continues to push upward under the control of the injection molding machine. At this time, the first ejector rod 361a will push a distance d4. The slider 362a slides upward to the right under the action of the first limiting block 363a and the second limiting block 364a. The slider 362a is disengaged from the first ejector rod 361a and no longer drives the first ejector plate 341 to move, but the first ejector rod 361a will push the second ejector plate 351 to continue moving a distance d5. Then, under the pushing of the second ejector plate 351, the second ejector rod 352 pushes the lens 4 to eject upward by a distance d5, so that the lens 4 is separated from the outer lower die core 13, completing the final demolding action.

[0069] In this embodiment, the ejection method of the mold design is quite different from the traditional structure. The mold design method of the present invention changes the die core ejection structure that originally controls the surface shape of the lens 4 to a die core that controls the outer diameter of the lens 4 as the ejection mechanism. The upper template 21 and the lower template 31 are integrally precision machined. The die core mounting holes of both can reach very high precision. The upper die core 11 is in the upper template 21, and the inner lower die core 12 is in the lower template 31, and there is no relative movement, which will not cause the die core and the template to slide for a long time and reduce their positioning, seriously affecting the eccentricity of the two surface shapes of the lens 4. This structure enables the outer lower die core 13 and the lower template 31 to have relative sliding to complete part of the demolding process. The relative moving distance d3 between the outer lower die core 13 and the lower template 31 is very small, so that it will not cause large-scale wear of the product. And the outer lower die core 13 mainly controls the outer diameter size of the lens 4 and does not participate in the installation and positioning of the lens 4. The lens 4 is installed and positioned by using the lens positioning slope for positioning and assembly. The positioning surface is formed by the upper die core 11 and the inner lower die core 12. This forming method will greatly improve the eccentricity of the two surface shapes of the lens 4, effectively reduce the wear of the die core, and improve the service life of the mold. Specific Embodiment 2:

[0071] Refer to Figure 10 As shown, the difference between this embodiment and Embodiment 1 is that the driving mechanism 36 does not adopt the first ejector rod 361a, the slider 362a, the first limiting block 363a, and the second limiting block 364a.

[0072] In this embodiment, the driving mechanism 36 includes a second pushing rod 361b, an elastic opening and closing structure 362b, and a second limiting member 363b. The elastic opening and closing structure 362b is arranged on the first ejector plate 341. The second pushing rod 361b is used to push the elastic opening and closing structure 362b and the first ejector plate 341 to move upward. One end of the second limiting member 363b is connected to the lower die base plate 33, and the other end is clamped with the first ejector plate 341 to limit the moving distance of the first ejector plate 341. When the first ejector plate 341 reaches the maximum moving distance, the second pushing rod 361b pushes the elastic opening and closing structure 362b to open and continues to move upward to act on the second ejector plate 351 to push the second ejector plate 351 to move upward.

[0073] In this embodiment, the elastic opening and closing structure 362b includes two elastic sliders arranged oppositely left and right. Compression springs are respectively connected to the left and right sides of the two elastic sliders. A bayonet cooperating with the second pushing rod 361b is arranged between the two elastic sliders.

[0074] In this embodiment, the pushing rod is used to push the elastic opening and closing structure 362b to move upward. After the elastic opening and closing structure 362b drives the first ejector plate 341 to move a distance d3, due to the obstruction of the second limiting member 363b, when the pushing rod continues to move, the two elastic sliders squeeze the compression springs toward both sides, the bayonets of the two elastic sliders expand, the pushing rod passes through the bayonets and acts on the second ejector plate 351, and the elastic opening and closing structure 362b will lose the thrust of the pushing rod, thereby realizing two-stage ejection. Specific Embodiment Three:

[0076] Referring to Figure 11 As shown, the difference between this embodiment and Embodiment One is that the driving mechanism 36 does not adopt the first pushing rod 361a, the slider 362a, the first limiting block 363a, and the second limiting block 364a.

[0077] In this embodiment, the driving mechanism 36 includes a third pushing rod 361c and a lever 362c. The third pushing rod 361c is used to push the first ejector plate 341 to move upward. The lever 362c includes a long side, a short side, and a node where the long side and the short side intersect. The node of the lever 362c is rotatably arranged on the first ejector plate 341. The end point of the short side abuts against the support plate 32, and the end point of the long side abuts against the second ejector plate 351.

[0078] The separation and ejection of the first ejection plate 341 and the second ejection plate 351 use the structural design of the toggle lever 362c. After the pusher rod is pushed for a distance d3, the toggle lever 362c contacts the support plate 32, so that the ejection speed of the second ejection plate 351 is greater than that of the first ejection plate 341, and the two-stage ejection and demolding of the product are realized by using the speed difference between the two. The greatest advantage of this demolding method is that the relative demolding speed gradually increases, avoiding the quality damage to the product caused by sudden acceleration demolding. Specific Embodiment Four:

[0080] Referring to Figure 12 As shown, the difference between this embodiment and Embodiment One is that the driving mechanism 36 does not adopt the first pusher rod 361a, the slider 362a, the first limiting block 363a, and the second limiting block 364a.

[0081] In this embodiment, the driving mechanism 36 includes a fourth pusher rod 361d, a first upper compression spring 362d, a first lower compression spring 363d, and a third limiting member 364d. The fourth pusher rod 361d is used to push the second ejection plate 351 to move upward. The top of the first upper compression spring 362d is connected to the support plate 32, and the bottom is connected to the second ejection plate 351. The top of the first lower compression spring 363d is connected to the first ejection plate 341, and the bottom is connected to the lower die base plate 33. One end of the third limiting member 364d is connected to the lower die base plate 33, and the other end is clamped with the first ejection plate 341 to limit the movement distance of the first ejection plate 341.

[0082] The key components for realizing staged demolding in this design example are two first upper compression springs 362d and first lower compression springs 363d with different stiffness coefficients and the third limiting member 364d. During the process of the pusher rod moving a distance d3, the pusher rod pushes the second ejection plate 351 to move and offsets the elastic force of the first upper compression spring 362d. At the same time, the first ejection plate 341 moves upward under the action of the first lower compression spring 363d. After the first ejection plate 341 is blocked by the third limiting member 364d and stops moving, the pusher rod continues to push the second ejection plate 351 to move, and finally completes the two-stage ejection and demolding of the product. Specific Embodiment Five:

[0084] Referring to Figure 13 As shown, the difference between this embodiment and Embodiment One is that the driving mechanism 36 does not adopt the first pusher rod 361a, the slider 362a, the first limiting block 363a, and the second limiting block 364a.

[0085] In this embodiment, the driving mechanism 36 includes a pull rod 361e, a second upper compression spring 362e, a second lower compression spring 363e, and a fourth limiting member 364e. The top of the pull rod 361e is connected to the second upper compression spring 362e, and the bottom is in contact with the first ejector plate 341 and is clamped with the second ejector plate 351. The top of the second upper compression spring 362e is connected to the upper die base plate 22, and the bottom is connected to the pull rod 361e. The top of the second lower compression spring 363e is connected to the first ejector plate 341, and the bottom is connected to the lower die base plate 33. One end of the fourth limiting member 364e is connected to the lower die base plate 33, and the other end is clamped with the first ejector plate 341 to limit the moving distance of the first ejector plate 341.

[0086] The key components for realizing staged demolding in this embodiment are the pull rod 361e, the second upper compression spring 362e, the second lower compression spring 363e, and the fourth limiting member 364e. During the first-stage distance of mold opening between the upper template 21 and the lower template 31, since the elastic force of the second upper compression spring 362e is greater than that of the second lower compression spring 363e, at this time, the pull rod 361e presses on the first ejector plate 341 and does not move. Subsequently, the upper template 21 continues to open a certain distance. At this time, due to the decrease in the elastic force of the second upper compression spring 362e, the second lower compression spring 363e will push up the first ejector plate 341 and the second ejector plate 351 to move. When the upper template 21 further opens, at this time, the pull rod 361e will pull the second ejector plate 351 to continue moving, and finally the product is demolded. Different from the above design example: Although this design is also a mold design mechanism for secondary ejection of the mold core, the power source for ejection is not the push rod but the opening of the upper template 21 driving the pull rod 361e. The advantage of this design example is that it can quickly connect the demolding of the product from the upper mold and the lower mold, and can be used in the actual production where the product-mold separation needs to be quickly realized after the molding of a certain type of product.

[0087] The present invention also provides an injection molding method for an optical lens injection mold, which is characterized by including the following steps:

[0088] Step 1, injecting through the sprue bushing 24 into the mold core structure 1, so that the lens 4 is formed in the mold core structure 1, and the ejector part 5 is formed between the sprue bushing 24 and the mold core structure 1;

[0089] Step 2, the upper template 21 moves upward to separate from the lower template 31. The upper demolding structure 23 abuts against the lens 4 and the ejector part 5. The upper mold core 11 moves upward following the upper template 21, so that the upper mold core 11 is separated from the upper surface of the lens 4, and the sprue bushing 24 is separated from the ejector part 5;

[0090] Step 3: The upper template 21 continues to move upward to a certain position, and the driving mechanism 36 drives the first ejection structure 34 to act, driving the outer lower die core 13 to move upward relative to the inner lower die core 12, so that the lower surface of the lens 4 is separated from the inner lower die core 12.

[0091] Step 4: The driving mechanism 36 drives the second ejection structure 35 to act, driving the ejection part 5 to move upward, so that the side surface of the lens 4 is separated from the outer lower die core 13, and the demolding is completed to remove the lens 4.

[0092] In the injection molding method of the present invention, during the entire demolding process, the upper die core 11 and the inner lower die core 12 that control the surface shape of the lens 4 do not move relative to the upper template 21 and the lower template 31 respectively, avoiding manufacturing errors caused by the movement of the die cores that control the surface shape. Only by making the outer lower die core 13 that controls the outer diameter move relative to the lower template 31 can demolding be achieved, improving the optical quality of the lens 4. The demolding method of the optical lens injection mold of the present invention first removes the surface shape area with a large demolding force through the overall uniform ejection action of the outer lower die core 13, and then removes the outer diameter area with a small demolding force, which can make the force on each part of the lens 4 more balanced during the demolding process, and can greatly reduce the demolding damage of the aspherical lens 4 with a large demolding force during the demolding process.

[0093] On the premise of no conflict, those skilled in the art can freely combine and superimpose the above additional technical features.

[0094] It can be understood that the present invention is described through some embodiments. Those skilled in the art know that without departing from the spirit and scope of the present invention, various changes or equivalent replacements can be made to these features and embodiments. In addition, under the teaching of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the optical lens injection mold of the present invention belong to the scope protected by the present invention.

Claims

1. An optical lens injection mold, characterized in that, It includes a mold core structure (1), an upper mold structure (2), and a lower mold structure (3). The mold core structure (1) includes an upper mold core (11), an inner lower mold core (12), and an outer lower mold core (13). The upper mold core (11), the inner lower mold core (12), and the outer lower mold core (13) respectively form the upper surface, the lower surface, and the side surface of the lens (4). The upper mold structure (2) includes an upper template (21), an upper mold base plate (22), an upper demolding structure (23), and a sprue bushing (24). The upper template (21) is fixedly connected to the upper mold base plate (22). The upper mold core (11) and the sprue bushing (24) are fixedly arranged in the upper template (21). A ejector part (5) connected to the lens (4) is formed between the sprue bushing (24) and the mold core structure (1). The upper demolding structure (23) includes an upper mold insert (231). A first elastic member (232) is arranged between the top of the upper mold insert (231) and the upper template (21) and is connected through the first elastic member (232). The bottom of the upper mold insert (231) abuts against the ejector part (5). The upper demolding structure (23) includes a first limiting member (233). One end of the first limiting member (233) is connected to the upper template (21), and the other end is clamped with the upper mold insert (231) to limit the moving distance of the upper mold insert (231). The upper demolding structure (23) is used to abut against the lens (4) and the ejector part (5) during demolding, so that the upper mold core (11) is separated from the upper surface of the lens (4), and the sprue bushing (24) is separated from the ejector part (5). The lower mold structure (3) includes a lower template (31), a support plate (32), a lower mold base plate (33), a first ejecting structure (34), a second ejecting structure (35), and a driving mechanism (36). The lower template (31) is arranged on the support plate (32). The support plate (32) is fixed on the lower mold base plate (33). The outer lower mold core (13) is fixed on the first ejecting structure (34). The inner lower mold core (12) is fixed on the support plate (32). The driving mechanism (36) is used to drive the first ejecting structure (34) to act to drive the outer lower mold core (13) to move upward relative to the inner lower mold core (12), so that the lower surface of the lens (4) is separated from the inner lower mold core (12). The second ejecting structure (35) is arranged below the ejector part (5). The driving mechanism (36) is used to drive the second ejecting structure (35) to act to drive the ejector part (5) to move upward, so that the side surface of the lens (4) is separated from the outer lower mold core (13).

2. The injection mold for an optical lens according to claim 1, characterized in that The first ejection structure (34) includes a first ejection plate (341) and a first ejection rod (342), and the second ejection structure (35) includes a second ejection plate (351) and a second ejection rod (352). The first ejection plate (341) and the second ejection plate (351) are arranged on the lower die base plate (33) so as to be movable up and down. The second ejection plate (351) abuts against the upper surface of the first ejection plate (341). The first ejection rod (342) is fixed on the first ejection plate (341), and the second ejection rod (352) is fixed on the second ejection plate (351).

3. An optical lens injection mold according to claim 2, characterized in that, The first ejection rod (342) is connected to the outer lower die core (13), and the second ejection rod (352) abuts against the ejection part (5).

4. An optical lens injection mold according to claim 2, characterized in that, The driving mechanism (36) includes a first pushing rod (361a), a slider (362a), a first limiting block (363a), and a second limiting block (364a). The first pushing rod (361a) passes through the first ejection plate (341) and abuts against the second ejection plate (351). The front and rear ends of the slider (362a) are respectively clamped with the first ejection plate (341). The left side of the slider (362a) is meshed and connected with the first pushing rod (361a). The upper end surface and the lower end surface of the slider (362a) are inclined upward to the right. The top of the first limiting block (363a) is fixed on the support plate (32), and the bottom abuts against the upper end surface of the slider (362a). The bottom of the second limiting block (364a) is fixed on the lower die base plate (33), and the top abuts against the lower end surface of the slider (362a). A chute for the slider (362a) to move upward to the right is formed between the first limiting block (363a) and the second limiting block (364a).

5. An optical lens injection mold according to claim 2, wherein The driving mechanism (36) includes a second pushing rod (361b), an elastic opening and closing structure (362b), and a second limiting member (363b). The elastic opening and closing structure (362b) is arranged on the first ejection plate (341). The second pushing rod (361b) is used to push the elastic opening and closing structure (362b) and the first ejection plate (341) to move upward. One end of the second limiting member (363b) is connected to the lower die base plate (33), and the other end is clamped with the first ejection plate (341) to limit the moving distance of the first ejection plate (341). When the first ejection plate (341) reaches the maximum moving distance, the second pushing rod (361b) pushes the elastic opening and closing structure (362b) to open and continues to move upward to act on the second ejection plate (351) to push the second ejection plate (351) to move upward.

6. An optical lens injection mold according to claim 5, characterized in that, The elastic opening and closing structure (362b) includes two elastic sliders arranged opposite to each other left and right. Compression springs are respectively connected to the left and right sides of the two elastic sliders. A bayonet matching with the second pushing rod (361b) is arranged between the two elastic sliders.

7. An optical lens injection mold according to claim 2, characterized in that, The driving mechanism (36) includes a third ejector rod (361c) and a toggle lever (362c). The third ejector rod (361c) is used to push the first ejector plate (341) to move upward. The toggle lever (362c) includes a long side, a short side, and a node where the long side intersects with the short side. The node of the toggle lever (362c) is rotatably arranged on the first ejector plate (341). The end point of the short side abuts against the support plate (32), and the end point of the long side abuts against the second ejector plate (351).

8. An optical lens injection mold according to claim 2, characterized in that, The driving mechanism (36) includes a fourth ejector rod (361d), a first upper compression spring (362d), a first lower compression spring (363d), and a third limiting member (364d). The fourth ejector rod (361d) is used to push the second ejector plate (351) to move upward. The top of the first upper compression spring (362d) is connected to the support plate (32), and the bottom is connected to the second ejector plate (351). The top of the first lower compression spring (363d) is connected to the first ejector plate (341), and the bottom is connected to the lower die base plate (33). One end of the third limiting member (364d) is connected to the lower die base plate (33), and the other end is clamped with the first ejector plate (341) to limit the moving distance of the first ejector plate (341).

9. An optical lens injection mold according to claim 2, characterized in that, The driving mechanism (36) includes a pull rod (361e), a second upper compression spring (362e), a second lower compression spring (363e), and a fourth limiting member (364e). The top of the pull rod (361e) is connected to the second upper compression spring (362e), and the bottom abuts against the first ejector plate (341) and is clamped with the second ejector plate (351). The top of the second upper compression spring (362e) is connected to the upper die base plate (22), and the bottom is connected to the pull rod (361e). The top of the second lower compression spring (363e) is connected to the first ejector plate (341), and the bottom is connected to the lower die base plate (33). One end of the fourth limiting member (364e) is connected to the lower die base plate (33), and the other end is clamped with the first ejector plate (341) to limit the moving distance of the first ejector plate (341).

10. An injection molding method for an optical lens injection mold, characterized in that, It includes an optical lens injection mold according to any one of claims 1-9. The injection method includes the following steps: Step 1: Inject through the sprue bushing (24) into the mold core structure (1) so that the lens (4) is formed in the mold core structure (1), and the ejector part (5) is formed between the sprue bushing (24) and the mold core structure (1). Step 2: The upper template (21) moves upward to separate from the lower template (31). The upper demolding structure (23) abuts against the lens (4) and the ejector part (5). The upper mold core (11) moves upward following the upper template (21) so that the upper mold core (11) is separated from the upper surface of the lens (4), and the sprue bushing (24) is separated from the ejector part (5). Step 3: The upper template (21) continues to move upward to a certain position, and the driving mechanism (36) drives the first ejection structure (34) to act, driving the outer lower die core (13) to move upward relative to the inner lower die core (12), so that the lower surface of the lens (4) is separated from the inner lower die core (12). Step 4: The driving mechanism (36) drives the second ejection structure (35) to act, driving the ejection part (5) to move upward, so that the side surface of the lens (4) is separated from the outer lower die core (13), completing the demolding to remove the lens (4).

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