Multi-direction back-off demolding mechanism for front mold of injection mold

Abstract

The utility model discloses a multidirectional back-off demoulding mechanism for a front mould of an injection mould, which comprises a pulling plate, a front mould insert and a pulling plate driving mechanism, one side of the front mould is provided with an accommodating groove, the pulling plate is arranged in the accommodating groove and can move along the mould opening and closing direction, one end of the front mould insert is fixedly connected with the pulling plate, and the other end of the front mould insert is fixedly connected with the pulling plate driving mechanism. The other end of the front mold insert is inserted into a front mold core fixed on the other side of the front mold; a plurality of elastic claws which are distributed in a central symmetry manner are arranged at the other end of the front mold insert, each elastic claw is provided with an elastic sheet part and a petal embedding part integrally connected to the elastic sheet part, and the petal embedding parts of the plurality of elastic claws are mutually closed to define an inverted buckle forming cavity; and the pulling plate driving mechanism is used for driving the pulling plate to drive the front mold insert to move during mold opening, so that the plurality of insert petal parts extend out of the front mold core and can be mutually opened under the elastic acting force of the respective elastic sheet parts. According to the utility model, normal demolding of products with multiple directions and densely distributed inverted buckles can be realized, the cost is reduced, the period is shortened, and the products are prevented from being adhered to the front mold core.

Description

Technical Field

[0001] The utility model relates to the technical field of injection molds, in particular to a front mold multi-directional undercut demoulding mechanism for an injection mold. Background Art

[0002] The principle of injection mold is: using the thermoplasticity of plastic, the molten plastic is injected into the mold cavity through the injection molding machine, and the plastic product is obtained after cooling and solidification. Specifically, when the plastic raw material is heated and melted in the injection molding machine, the screw of the injection molding machine will push the molten plastic forward and inject it into the mold cavity through the nozzle. In the mold, the plastic will be restricted by the shape and size of the mold cavity to form the desired product shape. Then, the mold will cool and solidify the plastic product through the cooling system to keep it in the desired shape and size. Finally, the mold opens and the molded plastic product is ejected, completing the entire injection molding process.

[0003] When there is an undercut on the product that is inconsistent with the demoulding direction, it is necessary to design an undercut demoulding structure in the mold; for a single undercut, by setting a slider on the mold, the undercut demoulding can be achieved by moving the slider, however, for multi-directional and dense undercuts (such as the one in the figure of the specification), Figure 1 As shown in the figure, there is no more space to set the slider, which makes it difficult to demould such products normally. The conventional practice is usually to disassemble and splice the product, which leads to high manufacturing cost, long cycle and poor aesthetics. Therefore, it is necessary to improve the existing technology to overcome the defects in the existing technology. Summary of the invention

[0004] The problem to be solved by the utility model is to provide a multi-directional undercut demoulding mechanism for a front mold of an injection mold, so as to overcome the defect that the existing injection mold cannot realize normal demoulding for products with multi-directional and relatively dense undercuts.

[0005] The utility model adopts the following technical scheme to solve the technical problems: a front mold multi-directional undercut demoulding mechanism for an injection mold, which is installed on the front mold of the injection mold, and comprises: a pull plate, a front mold insert and a pull plate driving mechanism, a side of the front mold facing away from the cavity of the injection mold is provided with a receiving groove, the pull plate is arranged in the receiving groove and can move along the direction of mold opening and closing, one end of the front mold insert is fixedly connected to the pull plate, and the other end of the front mold insert is inserted into the front mold core fixed on the other side of the front mold; the other end of the front mold insert is provided with a plurality of elastic claws distributed in a central symmetrical manner, the elastic claws are all provided with a spring sheet part and an insert petal part integrally connected to the spring sheet part, and the insert petal parts of the plurality of elastic claws are mutually closed to form an undercut molding cavity for molding the undercut part of the product; the pull plate driving mechanism is used to drive the pull plate to drive the front mold insert to move when opening the mold, so that the plurality of insert petal parts extend out of the front mold core and can be mutually opened under the elastic action force of their respective spring sheet parts.

[0006] As a further improvement of the present invention, the pull plate driving mechanism includes a plurality of return springs, and the plurality of return springs are elastically abutted against a side of the pull plate facing away from the cavity, so as to always apply an elastic force to the pull plate in the direction of the cavity.

[0007] As a further improvement of the present invention, the pull plate driving mechanism also includes a plurality of reset rods, one end of each of the reset rods is fixedly connected to the front mold, and the other end thereof protrudes upward through the pull plate, and the other end of each of the reset rods is provided with a stop platform, and a plurality of the reset springs are correspondingly mounted on the plurality of the reset rods and elastically abut against the stop platform.

[0008] As a further improvement of the present invention, the front mold core is provided with a through hole, a cylindrical wear-resistant insert sleeve is fixed in the through hole, and the plurality of insert petals are slidably placed in the wear-resistant insert sleeve.

[0009] As a further improvement of the utility model, a step is provided in the through hole, a hanging platform is provided on the top periphery of the wear-resistant insert sleeve, the hanging platform stops on the step, and the front mold presses the wear-resistant insert sleeve through a pressing ring.

[0010] As a further improvement of the utility model, the plurality of petal parts are all fan-shaped, and their outer diameters when closed match the inner diameter of the wear-resistant sleeve; an arc-shaped transition portion is provided at the connection position between the spring piece part and the petal part.

[0011] As a further improvement of the utility model, an insert guide sleeve is fixed in the front mold and slidably mounted on the front mold insert; the front mold is located in the accommodating groove and has multiple guide pillars installed, and the pull plate is slidably fitted on the guide pillars through the pull plate guide sleeve.

[0012] As a further improvement of the utility model, the injection mold includes a rear mold core arranged opposite to the front mold core, a plurality of mold lockers are installed on the rear mold core, and a plurality of mold locker bushings for corresponding plug-in cooperation with the plurality of mold lockers are fixed on the pull plate.

[0013] The beneficial effects of the utility model are as follows: the utility model provides a front mold multi-directional undercut demolding mechanism for an injection mold, wherein a front mold insert is installed on the front mold, and elastic claws arranged on the front mold insert are used to form undercuts with multiple directions and dense distribution. When the mold is opened, the inlay petals of the elastic claws are pushed out of the front mold core, and are opened accordingly under the elastic force of the spring sheet portion, thereby realizing normal demolding of products with multiple directions and dense distribution of undercuts, without the need to disassemble and splice the products, thereby reducing the manufacturing cost of the products, shortening the processing cycle, and improving the aesthetics of the products; at the same time, in the process of the pull plate driving mechanism driving the pull plate to drive the front mold insert to move toward the rear mold core, the front mold insert can also push the product out of the front mold core, thereby preventing the product from sticking to the front mold core, and improving the quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A three-dimensional diagram of a product molded by the injection mold of the utility model;

[0015] Figure 2 It is a three-dimensional diagram of the injection mold with a front mold multi-directional undercut demoulding mechanism of the utility model;

[0016] Figure 3 It is a top view of the injection mold with a front mold multi-directional undercut demoulding mechanism of the utility model;

[0017] Figure 4 For the utility model Figure 3 Sectional view in the AA direction;

[0018] Figure 5 For this utility model Figure 4 Enlarged view of middle C;

[0019] Figure 6 For the utility model Figure 3 Cross-sectional view in the BB direction;

[0020] Figure 7 It is a three-dimensional diagram of the multi-directional undercut demoulding mechanism of the front mold of the utility model;

[0021] Figure 8 It is a three-dimensional diagram of the front mold insert in the front mold multi-directional undercut demoulding mechanism of the utility model.

[0022] Combined with the accompanying drawings, the following description is given:

[0023] 1. Front mold; 101. Accommodating groove; 2. Pull plate; 3. Front mold insert; 31. Elastic claw; 311. Spring piece; 312. Insert petal; 313. Undercut molding cavity; 314. Arc transition part; 4. Front mold core; 401. Through hole; 402. Step; 5. Reset spring; 6. Reset rod; 7. Wear-resistant insert sleeve; 701. Hanging table; 8. Press ring; 9. Insert guide sleeve; 10. Guide column; 11. Pull plate guide sleeve; 12. Back mold core; 13. Clamp; 14. Clamp bushing; 15. Top plate; 16. Hot runner plate; 100. Product; 1001. Undercut part. DETAILED DESCRIPTION

[0024] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0025] See also Figures 1 to 8 The utility model provides a front mold multi-directional undercut demoulding mechanism of an injection mold, which is installed on the front mold 1 of the injection mold. Among them, the injection mold also includes a front mold core 4, a rear mold core 12, a top plate 15, a hot runner plate 16 and a rear mold (not shown in the figure), the hot runner plate 16 is fixed between the top plate 15 and the front mold 1, the front mold core 4 is fixed to the bottom of the front mold 1, the rear mold core 12 is fixed to the top of the rear mold and is arranged opposite to the front mold core 4, and a cavity for injection molding a product 100 can be enclosed between the front mold core 4 and the rear mold core 12. In addition, the injection mold can also include a rear mold ejection mechanism, etc., which are all existing conventional technologies, so they will not be described in detail.

[0026] Furthermore, the front mold multi-directional undercut demoulding mechanism of the injection mold of the utility model comprises: a pull plate 2, at least one front mold insert 3 and a pull plate driving mechanism, a receiving groove 101 is provided on the side of the front mold 1 facing away from the mold cavity of the injection mold, and the pull plate 2 is provided in the receiving groove 101 and can move along the mold opening and closing direction. The front mold insert 3 is cylindrical, and is inserted into the front mold 1 vertically, and the upper end of the front mold insert 3 is fixedly connected to the pull plate 2 by screws, and the lower end of the front mold insert 3 is inserted into the front mold core 4 to participate in the injection molding of the product 100.

[0027] It is understandable that the number of the front mold inserts 3 can be configured accordingly according to the number of the undercut portions 1001 on the product 100. Figure 1 As shown, the product 100 molded by the injection mold of this embodiment has three undercut parts 1001, and the injection mold has two cavities, so six front mold inserts 3 are provided, all of which are fixedly connected to the pull plate 2.

[0028] See also Figure 5 and Figure 8The lower end of the front mold insert 3 is provided with a plurality of elastic claws 31 distributed symmetrically in the center, each elastic claw 31 is provided with a spring sheet portion 311 and a petal portion 312 integrally connected to the spring sheet portion 311, and the petal portions 312 of the plurality of elastic claws 31 are mutually closed to form an undercut molding cavity 313, and the undercut molding cavity 313 is sealed at the top, open at the bottom and connected to the mold cavity, so as to form the undercut part 1001 of the product 100. The spring sheet portion 311 has a certain elastic deformation ability, and in a free state, the plurality of petal portions 312 are mutually opened under the elastic force of their respective spring sheet portions 311.

[0029] Among them, the number of elastic claws 31 can be configured accordingly according to the undercut direction on the undercut part 1001. For example, the undercut part 1001 of the product 100 in this embodiment has four undercut directions, so four elastic claws 31 are arranged in a centrally symmetrical distribution.

[0030] After the product 100 is injection molded, the front mold 1 and the rear mold are opened relative to each other. During this process, the pull plate driving mechanism drives the pull plate 2 to drive the front mold insert 3 to move toward the rear mold core 12, so that the multiple insert petals 312 extend out of the front mold core 4. The multiple insert petals 312 open to each other under the elastic force of their respective spring parts 311, and then detach from the undercut part 1001. The utility model installs a front mold insert 3 on the front mold 1, and utilizes the elastic claws 31 arranged on the front mold insert 3 to form multi-directional and densely distributed undercuts. When the mold is opened, the insert petal portion 312 of the elastic claw 31 is pushed out of the front mold core 4, and opens accordingly under the elastic force of the spring piece portion 311, thereby realizing normal demolding of the product with multi-directional and densely distributed undercuts, without the need to disassemble and splice the product 100, thereby reducing the manufacturing cost of the product 100, shortening the processing cycle, and improving the aesthetics of the product 100; at the same time, in the process of the pull plate driving mechanism driving the pull plate 2 to drive the front mold insert 3 to move toward the rear mold core 12, the front mold insert 3 can also push the product 100 out of the front mold core 4, thereby preventing the product 100 from sticking to the front mold core 4, and improving the quality of the product 100.

[0031] See also Figure 6 The pull plate driving mechanism includes a plurality of reset springs 5, which are elastically abutted against the side of the pull plate 2 facing away from the cavity, so as to always apply an elastic force toward the cavity to the pull plate 2. In addition, the pull plate driving mechanism also includes a plurality of reset rods 6, which are distributed vertically, and their lower ends are fixedly connected to the front mold 1, and their upper ends protrude upward through the pull plate 2, and the reset rods 6 and the pull plate 2 are in clearance fit; the plurality of reset springs 5 ​​are correspondingly mounted on the plurality of reset rods 6, and the upper ends of the reset rods 6 are provided with a stopper, and the two ends of the reset springs 5 ​​are elastically abutted against the stopper and the pull plate 2, respectively.

[0032] See also Figure 4 and Figure 7A plurality of clamping devices 13 are installed on the rear mold core 12, and a plurality of clamping device bushings 14 are fixed on the pull plate 2. The plurality of clamping device bushings 14 are vertically downwardly penetrated through the front mold 1 and the front mold core 4 and are correspondingly plugged and matched with the clamping devices 13. Among them, the clamping device 13 can be a nylon clamping device.

[0033] When the mold is opened, the mold locker 13 and the mold locker bushing 14 are used together with the return spring 5 to drive the pull plate 2 to move downward, thereby improving the reliability and stability of the movement of the pull plate 2. When the mold is closed, the mold locker 13 and the mold locker bushing 14 are used together to push the pull plate 2 to move upward and compress the return spring 5, while driving the front mold insert 3 so that the insert petal 312 of the elastic claw 31 is pushed back to the front mold core 4.

[0034] See also Figure 5 The front mold core 4 is provided with a through hole 401, a cylindrical wear-resistant insert 7 is fixed in the through hole 401, and a plurality of insert petals 312 are slidably placed in the wear-resistant insert 7. Specifically, a step 402 is provided in the through hole 401, a hanging platform 701 is provided on the top periphery of the wear-resistant insert 7, and the hanging platform 701 stops on the step 402. The front mold 1 presses the wear-resistant insert 7 through a pressing ring 8, thereby fixing the wear-resistant insert 7. Among them, the wear-resistant insert 7 is made of a material with good wear resistance, and its function is to ensure the service life.

[0035] In this embodiment, the plurality of petal portions 312 are all fan-shaped, and their outer diameters when closed match the inner diameter of the wear-resistant insert 7. It is worth mentioning that an arc-shaped transition portion 314 is provided at the connection position between the spring portion 311 and the petal portion 312 to ensure that the petal portion 312 can be smoothly retracted into the wear-resistant insert 7.

[0036] In addition, in order to ensure the stability of the front mold insert 3 sliding up and down, an insert guide sleeve 9 is fixed in the front mold 1, and the insert guide sleeve 9 is slidably mounted on the front mold insert 3. At the same time, in order to ensure the stability of the pull plate 2 sliding up and down, a plurality of guide pillars 10 are installed in the receiving groove 101 of the front mold 1, and the pull plate 2 is slidably fitted on the guide pillars 10 through the pull plate guide sleeve 11.

[0037] It can be seen that the front mold multi-directional undercut demolding mechanism of the injection mold of the utility model is equipped with a front mold insert 3 on the front mold 1, and uses the elastic claws 31 arranged on the front mold insert 3 to form multi-directional and densely distributed undercuts. When the mold is opened, the insert portion 312 of the elastic claw 31 is pushed out of the front mold core 4, and opens accordingly under the elastic force of the spring portion 311, thereby realizing normal demolding of the product with multi-directional and densely distributed undercuts, without the need to disassemble and splice the product 100, thereby reducing the manufacturing cost of the product 100, shortening the processing cycle, and improving the aesthetics of the product 100; at the same time, in the process of the pull plate driving mechanism driving the pull plate 2 to drive the front mold insert 3 to move toward the rear mold core 12, the front mold insert 3 can also push the product 100 out of the front mold core 4, thereby preventing the product 100 from sticking to the front mold core 4, thereby improving the quality of the product 100.

[0038] In the above description, many specific details are described to facilitate a full understanding of the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited by the specific implementation disclosed above. At the same time, any person familiar with the technical field can make many possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A front mold multi-directional undercut demoulding mechanism for an injection mold, mounted on a front mold (1) of the injection mold, characterized in that: include: A pull plate (2), a front mold insert (3) and a pull plate driving mechanism, wherein a receiving groove (101) is provided on the side of the front mold (1) facing away from the mold cavity of the injection mold, the pull plate (2) is arranged in the receiving groove (101) and can move along the mold opening and closing direction, one end of the front mold insert (3) is fixedly connected to the pull plate (2), and the other end of the front mold insert (3) is inserted into the front mold core (4) fixed on the other side of the front mold (1); the other end of the front mold insert (3) is provided with a plurality of elastic claws (31) distributed in a centrally symmetrical manner, The elastic claws (31) are each provided with a spring sheet portion (311) and a petal portion (312) integrally connected to the spring sheet portion (311); the petal portions (312) of the plurality of elastic claws (31) are mutually closed to form an undercut molding cavity (313) for molding an undercut portion of a product; the pull plate driving mechanism is used to drive the pull plate (2) to drive the front mold insert (3) to move when the mold is opened, so that the plurality of petal portions (312) extend out of the front mold core (4) and can open to each other under the elastic force of their respective spring sheet portions (311).

2. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 1, characterized in that: The pull plate driving mechanism comprises a plurality of return springs (5), and the plurality of return springs (5) are elastically abutted against a side of the pull plate (2) facing away from the cavity, so as to always apply an elastic force to the pull plate (2) in the direction of the cavity.

3. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 2, characterized in that: The pull plate driving mechanism also includes a plurality of reset rods (6), one end of each of the reset rods (6) is fixedly connected to the front mold (1), and the other end thereof passes through the pull plate (2) and protrudes upward, and a stop platform is provided at the other end of each of the reset rods (6), and a plurality of reset springs (5) are correspondingly mounted on the plurality of reset rods (6) and elastically abut against the stop platform.

4. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 1, characterized in that: The front mold core (4) is provided with a through hole (401), a cylindrical wear-resistant insert sleeve (7) is fixed in the through hole (401), and a plurality of insert petals (312) are slidably placed in the wear-resistant insert sleeve (7).

5. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 4, characterized in that: A step (402) is provided in the through hole (401), a hanging platform (701) is provided on the outer periphery of the top of the wear-resistant insert sleeve (7), the hanging platform (701) stops on the step (402), and the front mold (1) presses the wear-resistant insert sleeve (7) through a pressing ring (8).

6. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 4, characterized in that: The plurality of petal parts (312) are all in a fan-shaped shape, and their outer diameters when closed match the inner diameter of the wear-resistant insert sleeve (7); an arc-shaped transition part (314) is provided at the connection position between the spring piece part (311) and the petal part (312).

7. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 1, characterized in that: An insert guide sleeve (9) is fixed inside the front mold (1) and is slidably mounted on the front mold insert (3); the front mold (1) is located in the receiving groove (101) and is equipped with a plurality of guide pillars (10), and the pull plate (2) is slidably mounted on the guide pillars (10) via a pull plate guide sleeve (11).

8. The front mold multi-directional undercut demoulding mechanism of the injection mold according to claim 1, characterized in that: The injection mold comprises a rear mold core (12) arranged opposite to the front mold core (4), a plurality of mold lockers (13) are installed on the rear mold core (12), and a plurality of mold locker bushings (14) for corresponding plug-in cooperation with the plurality of mold lockers (13) are fixed on the pull plate (2).

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