Demolding device for backlight source

Abstract

The utility model discloses a demolding device for a backlight source, and relates to the technical field of injection mold demolding. The device comprises a base, a supporting column, an upper mold assembly, a lower mold assembly, a demolding mechanism and an ejection mechanism. The upper mold assembly and the lower mold assembly are correspondingly arranged, the demolding mechanism drives a lower mold to ascend and descend through meshing transmission of a threaded rod and a bevel gear, and mold opening and closing actions are achieved. The material ejecting mechanism converts rotary motion into linear lifting of an ejector rod through cam-rotating wheel transmission and is matched with a telescopic rod and a reset spring, so that stability and automatic reset in the ejecting process are guaranteed. According to the utility model, a single motor is adopted for driving, the linkage action of demolding and material ejection is synchronously controlled, and the problems of thin wall, light weight or easy residual and mold clamping of viscous materials caused by gravity demolding in the prior art are solved. And by optimizing a top plate guide structure and a linkage mechanism, the demolding efficiency and the product yield are improved, the equipment complexity is reduced, and the device is suitable for automatic production of high-precision backlight sources.

Description

Technical Field

[0001] This utility model relates to the field of injection mold demolding technology, and in particular to a demolding device for a backlight. Background Technology

[0002] In the field of backlight injection molding, the demolding device is the core equipment to ensure that the workpiece can be efficiently removed from the mold after molding.

[0003] Existing technology, such as Chinese Patent Application No. CN202421424043.8, discloses an LED backlight frame demolding device, including a base plate welded to the bottom of the inner cavity of a production equipment. The inner cavity of the production equipment is equipped with a mold assembly, which includes an open-hole fixing plate fixedly installed within the inner cavity of the production equipment. An upper mold is fixedly installed at the bottom of the open-hole fixing plate. Through the combined use of a cylinder, injection molding equipment, and the mold assembly, the backlight frame is injection molded. Through the combined use of a motor, a first gear, and a second gear, a rotating rod rotates, which in turn drives a first bevel gear to rotate. Through the combined use of a threaded rod, a first bevel gear, and a second bevel gear, the lower mold moves downward, thereby separating the lower mold from the upper mold. The molded backlight frame detaches from the inner cavity and falls to the top of the lower mold, completing the demolding process. This achieves the goal of demolding the backlight frame without the need for multiple devices, utilizing gravity to complete demolding simultaneously with mold opening.

[0004] The existing technology has the following defects: Although the LED backlight frame demolding device can realize the fully automatic process of opening and demolding, it only uses the lower mold to move down and gravity to make the backlight fall off. The demolding effect is poor for thin-walled, lightweight or sticky materials backlights, and residue or mold jamming is easy to occur. Therefore, there is room for improvement. Utility Model Content

[0005] To address the aforementioned technical problems, this utility model provides a demolding device for backlights, which solves the technical problem that existing demolding devices rely solely on the downward movement of the lower mold and gravity to detach the backlight, resulting in poor demolding effect for thin-walled, lightweight, or adhesive backlights, and the tendency to leave residue or jam the mold.

[0006] This utility model is achieved through the following technical solution:

[0007] A demolding device for a backlight includes a base, support columns, an upper mold assembly, a lower mold assembly, a demolding mechanism, and an ejector mechanism. The base has several support columns around its top perimeter, and the upper mold assembly is fixed to the top of each support column. The upper mold assembly includes an upper mold fixing plate, an upper mold, and an injection hole penetrating both. The upper mold fixing plate is fixedly connected to the support columns. The lower mold assembly includes a lower mold corresponding to the upper mold, and a lower mold fixing plate is fixedly installed at the bottom of the lower mold. The demolding mechanism and the ejector mechanism are located at the bottom of the lower mold assembly, forming a linkage mechanism for mold opening, demolding, and ejection.

[0008] Preferably, the demolding mechanism includes internally threaded cylinders symmetrically installed on both sides of the bottom of the lower mold fixing plate. A threaded rod is screwed into the internally threaded cylinder. A demolding base is rotatably installed at the bottom of the threaded rod through a bearing component. The demolding base is fixedly installed on the top of the base. A mounting bracket is provided on the surface of the demolding base. A connecting rod is rotatably connected inside the mounting bracket. A first helical gear is coaxially fixedly installed at both ends of the connecting rod. A second helical gear that meshes with the first helical gear is coaxially fixedly installed on the threaded rod.

[0009] Preferably, the surface of the demolding base is further provided with fixed seats located on both sides of the mounting bracket. The fixed seats are rotatably connected to the connecting rod to limit the axial movement of the connecting rod.

[0010] Preferably, a motor is fixedly installed inside the mounting bracket, the output shaft of the motor is connected to a first spur gear, and a second spur gear that meshes with the first spur gear is coaxially fixedly installed on the connecting rod.

[0011] Preferably, the ejector mechanism includes a top plate, with a plurality of ejector rods slidably connected to the lower mold at the center of the top of the top plate, telescopic rods connected to the bottom of the lower mold fixing plate fixedly installed around the top of the top plate, a mounting seat fixedly installed at the center of the bottom of the top plate, a rotating wheel rotatably connected inside the mounting seat, sliders fixedly installed on both sides of the bottom of the top plate, a limit post slidably installed at the bottom of the slider, and the limit post fixedly installed on the top of the fixing seat.

[0012] Preferably, both the fixed base and the inner side of the slider are provided with positioning posts, which are elastically connected by a return spring.

[0013] Preferably, a cam is also provided at the bottom of the rotating wheel at a corresponding position and is fixedly connected to the connecting rod; the outer edge contour of the cam and the contact surface with the rotating wheel are involute or arc-shaped, which is used to convert the rotational motion into the linear lifting and lowering of the top plate.

[0014] Preferably, the telescopic rod is a multi-stage hydraulic cylinder or pneumatic cylinder, with its top fixedly connected to the lower mold fixing plate and its bottom fixedly connected to the top plate, used to maintain the stability of the lower mold fixing plate during the ejection process.

[0015] The beneficial effects of this utility model are as follows:

[0016] 1. Synchronous control of demolding and ejection actions via a single motor-driven connecting rod: When the motor drives the connecting rod to rotate, the first helical gear at both ends meshes with the second helical gear on the threaded rod, causing the threaded rod to rotate and the lower mold fixing plate to rise and fall along the internal threaded cylinder, realizing mold closing and opening; simultaneously, the cam at the end of the connecting rod periodically pushes the rotating wheel at the bottom of the top plate with the rotation, driving the ejector rod to vertically eject the workpiece. This design achieves the time-series linkage of demolding lifting and ejection actions with a single power source, actively applying a controllable ejection force (not relying on gravity) during the mold opening stage. Especially for thin-walled / viscous backlights, the ejector rod vertically ejects into the cavity with a preset stroke, eliminating vacuum adsorption and adhesive forces between the product and the mold, significantly reducing the residue rate.

[0017] 2. Through the combined guidance of the telescopic rod and the return spring, the ejector rod is ensured to move vertically without wobbling during the ejection stage, avoiding friction damage with the mold cavity sidewall. At the same time, the ejector rod is forced to quickly return to its original position before mold closing, completely eliminating the risk of interference between the ejector rod and the closed mold. This mechanism requires no additional power or manual intervention, achieving automatic reset after ejection and shortening the production cycle. In addition, the spring preload is adjustable to adapt to different ejection resistance requirements, enhancing the versatility of the device.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the background art, the accompanying drawings used in the embodiments of this utility model or the background art will be described below.

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with this disclosure and, together with the specification, serve to illustrate the technical solutions disclosed in this utility model.

[0021] Figure 1 This is a schematic diagram of the overall structure of a demolding device for a backlight in this utility model.

[0022] Figure 2 This is a three-dimensional structural diagram of the demolding mechanism and the ejection mechanism in this utility model;

[0023] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0024] Figure 4 This is a three-dimensional structural diagram of the demolding mechanism and the ejection mechanism in this utility model from another perspective.

[0025] Legend: 1. Base; 2. Support column; 3. Upper mold assembly; 31. Injection hole; 32. Upper mold fixing plate; 33. Upper mold; 4. Lower mold assembly; 41. Lower mold; 42. Lower mold fixing plate; 5. Demolding mechanism; 51. Demolding base; 52. Bearing; 53. Threaded rod; 54. First helical gear; 55. Second helical gear; 56. Internal threaded cylinder; 57. Fixed seat; 58. Connecting rod; 59. Mounting bracket; 510. Motor; 511. First spur gear; 512. Second spur gear; 6. Ejector mechanism; 61. Cam; 62. Rotary wheel; 63. Mounting seat; 64. Top plate; 65. Telescopic rod; 66. Slider; 67. Limiting post; 68. Ejector rod; 69. Return spring; 610. Positioning post. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this utility model, it should be noted that the terms "center," "upper," and "lower" are used interchangeably.

[0029] The orientations or positional relationships indicated by terms such as "left," "right," "vertical," "horizontal," "inner," and "outer" are based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships commonly used when the product is in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0030] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0031] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0033] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.

[0034] Example 1

[0035] Please refer to Figures 1-4A demolding device for a backlight includes a base 1, support columns 2, an upper mold assembly 3, a lower mold assembly 4, a demolding mechanism 5, and an ejector mechanism 6. Several support columns 2 are installed around the top of the base 1, and the upper mold assembly 3 is mounted on the top of each support column 2. The upper mold assembly 3 includes an upper mold fixing plate 32, an upper mold 33, and an injection hole 31 penetrating both. The upper mold fixing plate 32 is fixed to the top of the support columns 2, and the upper mold 33 is fixed to the bottom center of the upper mold fixing plate 32. The lower mold assembly 4 includes a lower mold 41 corresponding to the bottom of the upper mold 33, and the lower mold fixing plate 42 is fixedly installed on the bottom of the lower mold 41. The demolding mechanism 5 includes internally threaded cylinders 56 symmetrically installed on both sides of the bottom of the lower mold fixing plate 42. Threaded rods 53 are threaded into the internally threaded cylinders 56. A demolding base 51 is rotatably mounted on the bottom via a bearing 52. The demolding base 51 is fixed to the top of the base 1. A mounting bracket 59 and fixed seats 57 located on both sides of the mounting bracket 59 are provided on the surface of the demolding base 51. A connecting rod 58 is rotatably connected inside the mounting bracket 59. A first helical gear 54 is coaxially fixedly mounted at both ends of the connecting rod 58. A second helical gear 55 that meshes with the first helical gear 54 is coaxially fixedly mounted on the threaded rod 53. The fixed seats 57 are rotatably connected to the connecting rod 58 to support the connecting rod 58 and prevent it from moving axially. A motor 510 is also installed inside the mounting bracket 59. A first spur gear 511 is connected to the output shaft of the motor 510. A second spur gear 512 that meshes with the first spur gear 511 is coaxially fixedly mounted on the connecting rod 58.

[0036] Please refer to Figures 1-4 To address the shortcomings of existing technologies that rely solely on the downward movement of the lower mold and gravity to detach the backlight, which results in poor demolding performance for thin-walled, lightweight, or sticky backlights and leads to residue or jamming, this application's demolding device further includes an ejector mechanism 6 located at the bottom of the lower mold assembly 4 for ejecting the molded part. The ejector mechanism 6 includes a top plate 64, with several ejector rods 68 positioned at the center of the top of the top plate 64. The tops of the ejector rods 68 are slidably connected to the lower mold assembly 4 for smoothly ejecting the injection molded part. Telescopic rods 65, which are fixedly connected to the bottom of the lower mold fixing plate 42, are fixedly installed around the top of the top plate 64. The coordinated use of multiple telescopic rods 65 provides better support for the bottom of the lower mold fixing plate 42, enhancing the stability of the lower mold 41 during injection molding. A mounting base 6 is fixedly installed at the center of the bottom of the top plate 64. 3. A rotating wheel 62 is rotatably connected inside the mounting base 63. Slider 66 is fixedly installed on both sides of the bottom of the top plate 64. Limiting post 67 is slidably installed on the bottom of the slider 66. The limiting post 67 is fixedly installed on the top of the fixed base 57. The fixed base 57 and the slider 66 are both provided with positioning posts 610. They are elastically connected by a return spring 69 to realize automatic reset after the material is ejected. A cam 61 is also provided at the corresponding position of the bottom of the rotating wheel 62 and is fixedly connected to the connecting rod 58. The top plate 64 is raised and lowered by rotating the cam 61.

[0037] The working principle of a demolding device for a backlight in this application is as follows:

[0038] Motor 510 starts and drives the first spur gear 511 to rotate. The first spur gear 511 meshes with the second spur gear 512 on the connecting rod 58, driving the connecting rod 58 to rotate. The first helical gears 54 at both ends of the connecting rod 58 rotate accordingly and mesh with the second helical gear 55 on the threaded rod 53. The second helical gear 55 drives the threaded rod 53 to rotate (limited by bearing 52, only rotating without vertical movement). During the mold closing stage: the threaded rod 53 engages with the internal threaded cylinder 56 at the bottom of the lower mold fixing plate 42. The rotation of the threaded rod 53 generates axial displacement, pushing the lower mold fixing plate 42 and the lower mold 41 upwards, closing with the upper mold 33 to complete the injection molding. During the mold opening and ejection stage: after injection molding and cooling, motor 510 reverses, the threaded rod 53 rotates in the opposite direction, and the lower mold fixing plate 42 drives the lower mold 41 downwards, separating it from the upper mold 33 and forming a demolding space. Simultaneously, when the connecting rod 58 rotates, the cam 61 fixed at its end rotates synchronously. The outer edge of the cam 61 periodically pushes the rotating wheel 62 of the ejector mechanism 6, causing the top plate 64 to rise vertically along the limiting post 67. When the top plate 64 rises, the ejector rod 68 at its top enters the cavity of the lower mold 41, smoothly ejecting the formed backlight. The telescopic rod 65 extends synchronously to ensure the stability of the lower mold fixing plate 42 during the lifting and lowering of the top plate 64. In the reset stage, during the mold closing process, the lower mold fixing plate 42 is driven upward by the threaded rod 53. Through the rigidly connected telescopic rod 65, the top plate 64 is forced to rise synchronously. The rotating wheel 62 rises vertically with the top plate 64 and leaves the rotation trajectory of the cam 61. After leaving, the reset spring 69 contracts, pulling the slider 66 down along the limiting post 67, causing the top plate 64 and the ejector rod 68 to descend smoothly to the initial position. The ejector rod 68 is completely retracted to the bottom of the lower mold 41. During this process, the cam 61 rotates continuously with the connecting rod 58, but because the rotating wheel 62 has disengaged from the contact, the ejector mechanism 6 remains in the reset state until the lower mold fixing plate 42 moves down when the mold is opened, and the rotating wheel 62 re-enters the working area of ​​the cam 61. The demolding and ejection actions are synchronously controlled by a single motor 510 driving the connecting rod 58. During the mold opening stage, a controllable ejection force is actively applied (not relying on gravity). Especially for thin-walled / viscous backlights, the ejector rod 68 is vertically ejected into the cavity with a preset stroke, eliminating vacuum adsorption and adhesive forces between the product and the mold, thus significantly reducing the residue rate. At the same time, through the combined guidance of the telescopic rod 65 and the return spring 69, the vertical movement of the ejector rod 68 is ensured without deflection during the ejection stage, avoiding friction damage with the side wall of the mold cavity. In addition, the ejector rod 68 is forced to quickly return to its original position before the mold closes, completely eliminating the risk of interference between the ejector rod 68 and the closed mold. This mechanism requires no additional power or manual intervention, achieving automatic reset after ejection and shortening the production cycle. Meanwhile, the spring preload is adjustable to adapt to different ejection resistance requirements, enhancing the versatility of the device.

[0039] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A demolding device for a backlight, characterized in that: The system includes a base, support columns, an upper mold assembly, a lower mold assembly, a demolding mechanism, and an ejector mechanism. The base has several support columns around its top perimeter, with the upper mold assembly fixed to the top of each support column. The upper mold assembly includes an upper mold fixing plate, an upper mold, and injection holes penetrating both. The upper mold fixing plate is fixedly connected to the support columns. The lower mold assembly includes a lower mold corresponding to the upper mold, with a lower mold fixing plate fixedly installed at the bottom of the lower mold. The demolding mechanism and the ejector mechanism are located at the bottom of the lower mold assembly, forming a linkage mechanism for mold opening, demolding, and ejection. The ejector mechanism includes a top plate, with several ejector rods slidably connected to the lower mold in the center of the top of the top plate. Telescopic rods connected to the bottom of the lower mold fixing plate are fixedly installed around the top perimeter of the top of the top plate, and a mounting base is fixedly installed in the center of the bottom of the top plate.

2. The demolding device for a backlight according to claim 1, characterized in that: The demolding mechanism includes internally threaded cylinders mounted on both sides of the bottom of the lower mold fixing plate. A threaded rod is threaded into the internally threaded cylinder. A demolding base is rotatably mounted on the bottom of the threaded rod via a bearing. The demolding base is fixedly mounted on the top of the base. A mounting bracket is provided on the surface of the demolding base. A connecting rod is rotatably connected inside the mounting bracket. A first helical gear is coaxially fixedly mounted on both ends of the connecting rod. A second helical gear that meshes with the first helical gear is coaxially fixedly mounted on the threaded rod.

3. A demolding device for a backlight according to claim 2, characterized in that: The surface of the demolding base is also provided with fixed seats located on both sides of the mounting frame. The fixed seats are rotatably connected to the connecting rod to limit the axial movement of the connecting rod.

4. A demolding device for a backlight according to claim 2, characterized in that: A motor is fixedly installed inside the mounting bracket. The output shaft of the motor is connected to a first spur gear. A second spur gear that meshes with the first spur gear is coaxially fixedly installed on the connecting rod.

5. A demolding device for a backlight according to claim 3, characterized in that: A rotating wheel is rotatably connected inside the mounting base. Slider blocks are fixedly installed on both sides of the bottom of the top plate. Limiting posts are slidably installed at the bottom of the sliders, and the limiting posts are fixedly installed on the top of the mounting base.

6. A demolding device for a backlight according to claim 5, characterized in that: Both the fixed base and the inner side of the slider are provided with positioning posts, which are elastically connected by a return spring.

7. A demolding device for a backlight according to claim 5, characterized in that: A cam, which is fixedly connected to the connecting rod, is also provided at the bottom of the rotating wheel; the outer edge contour of the cam and the contact surface with the rotating wheel are involute or arc-shaped, which are used to convert the rotational motion into the linear lifting and lowering of the top plate.

8. A demolding device for a backlight according to claim 7, characterized in that: The telescopic rod is a multi-stage hydraulic cylinder or pneumatic cylinder, with its top fixedly connected to the lower mold fixing plate and its bottom fixedly connected to the top plate, used to maintain the stability of the lower mold fixing plate during the ejection process.

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