Insert for mold core pulling, mold and working method

Abstract

The invention relates to an insert for mold core pulling, a mold and a working method.The insert comprises an insert body, the insert body is provided with a first channel, the axis of the first channel is arranged in the first direction, the top face of the first channel extends to the top face of the insert body, the bottom end of the first channel communicates with a second channel, and the axis of the second channel is arranged in the second direction and penetrates through the insert body; the first direction is the mold closing and opening direction of the mold, the second direction is perpendicular to the first direction, a guide pressing block is slidably connected into the first channel, a core pulling body is slidably connected into the second channel and comprises a moving structure slidably connected with the second channel, and a forming structure is arranged at the end of one side of the moving structure. The bottom end of the guide pressing block is provided with a shifting block forming a set acute angle with the axis of the guide pressing block, the top face of the moving structure is provided with a groove matched with the shifting block, the insert does not need to be assembled with a split part, machining and manufacturing cost is prevented from being increased, and production efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of mold development technology, specifically to an insert for mold core pulling, a mold, and a working method. Background Technology

[0002] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art.

[0003] Currently, when pulling cores in molds, the core-pulling mechanism uses a slanted ejector or a slider mechanism. When the mold is demolded, the vertical movement of the mold is converted into the lateral movement of the slider, thereby achieving core pulling. However, in some current injection molded products, there is an undercut structure along the core-pulling direction. The slider needs to have a cavity that matches the undercut structure. If a traditional slanted ejector or slider core-pulling mechanism is used, the slider will interfere with the undercut structure along the core-pulling direction when it moves. Therefore, the traditional core-pulling mechanism cannot be used, forcing the injection molded product to abandon the ideal structure. Alternatively, the part of the injection molded product that cannot be core-pulled is replaced by a split part. The split part needs to be processed and then reassembled, which increases the processing and manufacturing cost and reduces production efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide an insert for core pulling in molds, a mold, and a working method, which meets the production and processing needs of injection molded products with undercut structures along the core pulling direction.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, embodiments of the present invention provide a mold core-pulling insert, including an insert body, the insert body having a first channel, the axis of the first channel being arranged along a first direction, the top surface of the first channel extending to the top surface of the insert body, the bottom end communicating with a second channel, the axis of the second channel being arranged along a second direction and penetrating the insert body, the first direction being the mold closing and opening direction, the second direction being perpendicular to the first direction, a guide pressure block being slidably connected in the first channel, a core-pulling body being slidably connected in the second channel, the core-pulling body including a moving structure slidably connected to the second channel, a forming structure being provided on one end of the moving structure, a lever being provided at the bottom end of the guide pressure block at a set acute angle to its axis, and a groove matching the lever being provided on the top surface of the moving structure; The guide block moves in the first direction, which, through the cooperation of the push block and the groove surface, drives the core-pulling body to move in the second direction.

[0006] Optionally, the guide block is elastically connected to the insert body via an elastic element.

[0007] Optionally, the guide block includes a guide post, with a pressure head coaxially mounted at the top of the guide post. The diameter of the circumference of the pressure head is larger than the diameter of the circumference of the guide post. A lever is mounted at the bottom of the guide post. Correspondingly, the first channel includes a first channel portion that matches the pressure head and a second channel portion that matches the guide post. The elastic element is a spring fitted around the outer circumference of the guide post. One end of the spring is connected to the bottom surface of the pressure head, and the other end is connected to the stepped surface formed by the first channel portion and the second channel portion.

[0008] Optionally, the cross-section of the guide post perpendicular to its axis is D-shaped, and correspondingly, the cross-section of the second channel portion perpendicular to its axis adopts a D-shaped shape that matches the guide post.

[0009] Optionally, a limiting block is provided on one side of the top of the first channel, and correspondingly, a protrusion corresponding to the limiting block is provided on one side of the peripheral surface of the guide block. The protrusion can contact the limiting block to limit the movement of the guide block away from the second channel.

[0010] Optionally, the top surface of the insert body is provided with a limiting block mounting groove, and the limiting block is fixed in the limiting block mounting groove.

[0011] Optionally, the insert body is provided with fixing holes, and the insert body can be fixedly connected to the mold through the fixing holes and fixing bolts.

[0012] Optionally, the thickness of the pry bar is 0.1-0.5 mm less than the width of the groove.

[0013] Secondly, embodiments of the present invention provide a mold, including a moving mold and a fixed mold, wherein the fixed mold is provided with the mold core-pulling insert described in the first aspect.

[0014] Thirdly, embodiments of the present invention provide a method for operating the mold described in the second aspect, comprising the following steps: The moving mold moves toward the fixed mold in the first direction. After the parting surface of the moving mold contacts the top surface of the guide block, it drives the guide block to move until the parting surface of the moving mold contacts the top surface of the insert body, thus completing the mold closing. During the movement of the guide block, the push block at the bottom of the guide block cooperates with the groove surface of the core-pulling body groove. The movement of the guide block causes the core-pulling body to move in the second direction, and the molding structure extends to the outside of the insert body. Injection molding of injection molded products; After injection molding is completed, the moving mold moves away from the fixed mold, and the guide block also moves away from the second channel. With the cooperation of the push block and the groove surface, the core pulling body moves along the second direction, and the molding structure retracts into the second channel. Eject the injection molded product from the fixed mold.

[0015] The beneficial effects of this invention are as follows: 1. The mold insert, mold, and working method of the present invention are provided with a first channel and a second channel. A guide block is slidably provided in the first channel, and a core-pulling body is slidably provided in the second channel. A push block is provided at the bottom end of the guide block, and the core-pulling body is provided with a groove that matches the push block. The movement of the guide block along the first direction can be converted into the movement of the core-pulling body along the second direction through the cooperation of the push block and the groove surface, thereby realizing core pulling. During the core pulling process, only the core-pulling body moves along the second direction, and the insert body as a whole does not move along the core pulling direction. When the insert body is used to form an undercut structure distributed along the core pulling direction, the core pulling movement will not interfere with the undercut structure, thereby enabling the mold to be applied to the injection molding of injection molded products with undercut structures along the core pulling direction. There is no need to assemble and disassemble parts later, avoiding the increase in processing and manufacturing costs and improving production efficiency.

[0016] 2. The mold core-pulling insert, mold, and working method of the present invention achieve core-pulling movement through the cooperation of the push block and the groove. The push block and the core-pulling body occupy little space, eliminating the need to set up a mold inclined top or slider. The structure is simple and the manufacturing cost is low. It solves the problem that the inclined top or slider of the mold in a small space cannot be realized, thereby improving the feasibility of mold development with undercut structure in a small space. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the interaction between Embodiment 1 of the present invention and an injection-molded product; Figure 3 This is a top view of Embodiment 1 of the present invention in conjunction with an injection-molded product; Figure 4 This is the present invention. Figure 3 A schematic diagram of the section along direction A; Figure 5 This is the present invention. Figure 3 Schematic diagram of the B-direction section; Figure 6 This is a schematic diagram of the insert body structure in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the guide block structure in Embodiment 1 of the present invention; Figure 8 This is a schematic diagram of the core-pulling main structure of Embodiment 1 of the present invention; Figure 9 This is a schematic diagram of the insert state under the moving mold and fixed mold separation states in Embodiment 2 of the present invention; Among them, 1. First inverted structure, 2. Second inverted structure, 3. Insert body, 4. Injection molded product, 5. First channel, 6. Second channel, 7. Guide block, 8. Limiting block, 9. Long groove, 10. Limiting block mounting groove, 11. Pulley, 12. Spring, 13. Motion structure, 14. Molding structure, 15. Groove, 16. Fixing hole, 17. Fixing bolt; 5-1. First passage section; 5-2. Second passage section; 7-1. Indenter, 7-2. Protrusion, 7-3. Guide post. Detailed Implementation

[0019] For ease of description, the words "upper" and "lower" appearing in this invention only indicate that they are consistent with the upper and lower directions of the accompanying drawings and do not limit the structure. They are merely for the purpose of facilitating the description of this invention and simplifying the description, and do not indicate or imply that the device or component 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 this invention.

[0020] In this embodiment, the mold closing and opening directions of the moving mold and the fixed mold are defined as the first direction, and the direction perpendicular to the first direction is defined as the second direction.

[0021] Example 1 This embodiment provides a mold core-pulling insert for injection molding of injection molded products. The injection molded product 4 has a first undercut structure 1 and a second undercut structure 2 at its top, which are arranged along the core-pulling direction. The bottom of the injection molded product has a through hole, requiring a corresponding molding structure for forming.

[0022] like Figures 1-6 As shown, the insert for core pulling in the mold includes an insert body 3, which is used to fix and connect with the fixed mold of the mold. The insert body 3 has a first channel 5, the axis of the first channel 5 is set along a first direction, the top end of the first channel 5 extends to the top surface of the insert body 3, the bottom end of the first channel 5 is connected to a second channel 6, the axis of the second channel 6 is set along a second direction, and the second channel 6 penetrates the entire insert body 3 along the second direction.

[0023] In the top surface of the insert body 3, the top surface portion located on one side of the first channel 5 is provided with an elongated groove 9, which is used to cooperate with the side surface of the insert body 3 on that side to form a first undercut structure 1. The other side of the top surface of the insert body 3 and the other side surface are used to form a second undercut structure 2.

[0024] In this embodiment, the first channel 5 includes a first channel portion 5-1 and a second channel portion 5-2 arranged coaxially in sequence. The top end of the first channel portion 5-1 extends to the top surface of the insert body 3, and the bottom end communicates with the top end of the second channel portion 5-2. The bottom end of the second channel portion 5-2 communicates with the second channel 6.

[0025] The first channel section 5-1 is a cylindrical channel, and the cross section of the second channel section 5-2 perpendicular to its axis is D-shaped, which is equivalent to a circular cross section with a part cut off to form a D-shaped shape. The circumference of the cross section of the second channel section 5-2 perpendicular to its axis is coaxial with that of the first channel section 5-1.

[0026] The first channel 5 is provided with a guide block 7, which is slidably connected to the first channel 5 and can move in the first direction within the first channel 5.

[0027] Specifically, the guide block 7 includes a pressure head 7-1. The pressure head 7-1 adopts a cylindrical structure that matches the first channel portion 5-1. The pressure head 7-1 is slidably connected to the first channel portion 5-1. A portion of the pressure head 7-1 is cut off from one side from the top surface to form a protrusion 7-2 located on one side of the bottom of the pressure head. That is, the cross-sectional shape of the pressure head perpendicular to its axis is D-shaped. At the same time, a protrusion 7-2 is provided at the bottom end of the side plane of the pressure head.

[0028] Correspondingly, a limiting block 8 matching the protrusion 7-2 is provided on one side of the top of the first channel 5-1. When the guide block 7 moves away from the second channel 6, it can move until the protrusion 7-2 contacts the limiting block 8, thereby limiting the movement of the guide block 7 away from the second channel 6 by the cooperation of the limiting block 9 and the protrusion 7-2.

[0029] Furthermore, a limiting block mounting groove 10 is provided on one side of the top of the first channel section 5-1, which is opened on the top surface of the insert body 3. The limiting block 8 is placed in the limiting block mounting groove 10 and fixedly connected to the insert body 3 by screws. In order to avoid the limiting block 8 from hindering the parting surface of the moving mold from fitting with the top surface of the insert body 3, the thickness of the limiting block 8 is not greater than the depth of the limiting block mounting groove 10, so that the limiting block 8 will not protrude from the top surface of the insert body 3. At the same time, the head of the screw is located in the recess opened on the top surface of the limiting block 8, so that the head of the screw will not protrude from the upper surface of the limiting block 8.

[0030] The bottom surface of the pressure head 7-1 is integrally fixedly connected to the top of the guide post 7-3. The cross-sectional shape of the guide post 7-3 perpendicular to its axis matches the second channel part 5-2 and is also D-shaped. The guide post 7-3 and the second channel part 5-2 are slidably connected. Because its cross-section is D-shaped, the entire guide pressure block 7 can only move along its axis and will not rotate along its axis.

[0031] like Figure 7 As shown, the bottom end face of the guide post 7-3 is provided with a lever 11. The lever 11 is set at a set acute angle with the axis of the guide pressure block 7, and the lever 11 is inclined along the core pulling direction from top to bottom.

[0032] Furthermore, the acute angle is set to 18°-22°, which can be set by those skilled in the art according to actual needs, and will not be described in detail here.

[0033] An elastic element is provided between the guide block 7 and the insert body 3 so that the guide block and the insert body 3 are elastically connected.

[0034] In this embodiment, the elastic element is a spring 12. The spring 12 is sleeved on the outer periphery of the guide post 7-3. One end of the spring 12 is fixedly connected to the bottom surface of the pressure head 7-1, and the other end is fixedly connected to the stepped surface formed between the first channel portion 5-1 and the second channel portion 5-2. By setting the spring 12, an elastic force away from the second channel 6 can be applied to the guide pressure block 7.

[0035] In this embodiment, the spring 12 can be selected according to actual needs. Its elastic force needs to be more than 1.5 times greater than the minimum driving force for driving the guide block 7 to move upward. Those skilled in the art can determine the spring parameters according to actual needs, which will not be described in detail here.

[0036] The second channel 6 is a cylindrical channel with a core-pulling body slidably connected inside. The core-pulling body includes a moving structure 13, which is a cylindrical structure that matches the cylindrical channel. One end of the core-pulling body is provided with a molding structure 14. In this embodiment, the molding structure 14 is used to form a hole. Therefore, the molding structure 14 is a cylindrical structure. During injection molding, the molding structure 14 extends to the outside of the second channel 6, that is, to the outside of the insert body 3, to form a through hole in the injection molded product.

[0037] like Figure 8 As shown, the surface of the motion structure 13 is provided with a groove 15 that matches the lever 11. The axis of the groove 15 is set at a set acute angle with the first direction. The set acute angle is 18°-22°. The degree of the set acute angle between the axis of the groove 15 and the first direction is the same as the degree of the set acute angle between the lever 11 and the first direction, so that the lever 11 can be embedded in the groove 15.

[0038] Furthermore, the thickness of the push block 11 is less than the width of the groove 15, and the thickness of the push block 11 is 0.1mm-0.5mm less than the width of the groove 15.

[0039] In this embodiment, one side of the push block 11 is defined as a beveled surface and the other side is defined as a counter-pull surface. The beveled surface is close to the side of the forming structure 14. When the guide block 7 moves downward, the beveled surface first contacts the groove surface of the groove 15. The guide block 7 continues to move downward. Under the combined action of the beveled surface and the groove 15, the moving structure 13 moves along the axis of the second channel 6, so that the forming structure 14 can extend to the outside of the insert body 3.

[0040] When the wire pressure block 7 moves upward, the counter-pulling surface contacts the groove surface on the other side of the groove 15, and the guide pressure block 7 continues to move upward. Under the combined action of the counter-pulling surface and the groove surface of the groove 15, the moving structure 13 moves in the opposite direction along the axis of the second channel 6, thereby causing the forming structure 14 to retract into the interior of the second channel 6.

[0041] Furthermore, a limiting block mounting groove 10 is provided on the top surface of the insert body 3 on one side of the first channel 5, and a fixing hole 16 is provided on the top surface of the insert on the other side. The fixing hole 16 is provided through the insert body 3 along the first direction. The fixing hole 16 includes a countersunk hole on the top surface of the insert body 3 and a cylindrical hole extending to the countersunk hole at the top end. The bottom end of the cylindrical hole extends to the bottom surface of the insert body 3.

[0042] The insert body 3 can be fixedly connected to the fixed mold of the mold through the fixing hole 16 and the fixing bolt 17, wherein the thickness of the head of the fixing bolt is not greater than the depth of the countersunk hole so that after the insert body is fixed to the fixed mold, the head of the fixing bolt will not protrude from the top surface of the insert body.

[0043] Example 2 This embodiment provides a mold, including a fixed mold and a moving mold, and also includes the mold core-pulling insert described in Embodiment 1. The top surface of the insert body 3 can fit with the parting surface of the moving mold. The insert body 3 is fixed in the insert mounting cavity of the fixed mold through fixing holes 16 and fixing bolts 17. The fixed mold and the moving mold are both provided with molding cavities that match the injection molded product.

[0044] The remaining structure of the mold can be achieved using existing technology, and will not be described in detail here.

[0045] Example 3 This embodiment provides a method for operating the mold described in Embodiment 2, including the following steps: Mold closing: The moving mold moves toward the fixed mold. When the parting surface of the moving mold contacts the top surface of the pressure head 7-1, the moving mold continues to move toward the fixed mold, thereby driving the guide pressure block 7 to move toward the second channel 6. The beveled surface of the push block 11 contacts the groove surface of the groove 15, and the guide pressure block moves. Through the cooperation of the beveled surface and the groove surface of the groove 15, the moving structure 13 moves along the axis of the second channel 6, so that the molding structure 14 extends to the outside of the insert body 3. When the parting surface of the moving mold contacts the top surface of the insert body 3, the moving mold stops moving and the mold closing is completed. At this time, the moving mold, the fixed mold and the insert body form a product cavity for injection molding.

[0046] Step 2: Inject the molded product into shape using the product cavity. The injection molding method can be any existing technology and will not be described in detail here.

[0047] Step 3: As shown in 9, after injection molding is completed, the moving mold moves away from the fixed mold. The parting surface of the moving mold separates from the top surface of the pressure head 7-1. Under the elastic force of the spring 12, the guide pressure block 7 moves away from the second channel 6. The counter-pushing surface of the push block 11 cooperates with the groove surface of the groove 15. With the movement of the guide pressure block 7, the moving structure 13 is driven to move in the opposite direction along the axis of the second channel 6, that is, along the core pulling direction. The molding structure 14 retracts into the second channel 6. After the protrusion 7-2 of the guide pressure block 7 contacts the limiting block 8, the guide pressure block 7 stops moving, and the molding structure 14 is separated from the injection molded product.

[0048] In this embodiment, the core-pulling stroke S (the movement distance of the core-pulling body) is related to the guide block stroke H as follows: S = H × tanθ θ is the set acute angle between the axis of the toggle block and the axis of the first channel. The core-pulling stroke S is greater than the axial length A of the forming structure.

[0049] Step 4: Eject the injection molded part from the fixed mold to complete the production of the injection molded part. The ejection method can use existing technology and will not be described in detail here.

[0050] Using the mold of this embodiment, the movement of the guide block along the first direction can be transformed into the movement of the core-pulling body along the second direction through the cooperation of the push block and the groove surface, thereby realizing core pulling. During the core pulling process, only the core-pulling body moves along the second direction, and the insert body as a whole does not move along the core pulling direction. The core pulling movement will not cause interference between the insert body and the first and second undercut structures, thus enabling the mold to be applied to the injection molding of injection molded products with undercut structures along the core pulling direction. There is no need to assemble and disassemble parts later, avoiding the increase in processing and manufacturing costs and improving production efficiency. At the same time, the core pulling movement is realized through the cooperation of the push block and the groove. The push block and the core pulling body occupy little space, eliminating the need to set up mold slant tops or sliders. The structure is simple and the manufacturing cost is low, solving the problem that slant tops or sliders cannot be implemented in small space molds, thereby improving the feasibility of mold development for undercut structures in small spaces.

[0051] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An insert for core pulling in a mold, characterized in that, The device includes an insert body, which has a first channel. The axis of the first channel is set along a first direction. The top surface of the first channel extends to the top surface of the insert body, and the bottom end is connected to a second channel. The axis of the second channel is set along a second direction and passes through the insert body. The first direction is the mold closing and opening direction. The second direction is perpendicular to the first direction. A guide block is slidably connected in the first channel. A core-pulling body is slidably connected in the second channel. The core-pulling body includes a moving structure slidably connected to the second channel. A forming structure is provided at one end of the moving structure. A paddle block is provided at the bottom end of the guide block at a set acute angle with its axis. The top surface of the moving structure is provided with a groove that matches the paddle block. The guide block moves in the first direction, which, through the cooperation of the push block and the groove surface, drives the core-pulling body to move in the second direction.

2. The insert for core pulling in a mold as described in claim 1, characterized in that, The guide block is elastically connected to the insert body through an elastic element.

3. The insert for core pulling in a mold as described in claim 2, characterized in that, The guide block includes a guide post, with a pressure head coaxially mounted at the top of the guide post. The diameter of the circumference of the pressure head is larger than the diameter of the circumference of the guide post. A lever is mounted at the bottom of the guide post. Correspondingly, the first channel includes a first channel portion that matches the pressure head and a second channel portion that matches the guide post. The elastic element is a spring fitted around the outer circumference of the guide post. One end of the spring is connected to the bottom surface of the pressure head, and the other end is connected to the stepped surface formed by the first channel portion and the second channel portion.

4. The insert for core pulling in a mold as described in claim 3, characterized in that, The cross-section of the guide post perpendicular to its axis is D-shaped, and correspondingly, the cross-section of the second channel portion perpendicular to its axis adopts a D-shaped shape that matches the guide post.

5. The insert for core pulling in a mold as described in claim 1, characterized in that, A limiting block is provided on one side of the top of the first channel. Correspondingly, a protrusion corresponding to the limiting block is provided on one side of the peripheral surface of the guide block. The protrusion can contact the limiting block to limit the movement of the guide block away from the second channel.

6. The insert for core pulling in a mold as described in claim 5, characterized in that, The top surface of the insert body is provided with a limiting block mounting groove, and the limiting block is fixed in the limiting block mounting groove.

7. The insert for core pulling in a mold as described in claim 1, characterized in that, The insert body has fixing holes, and the insert body can be fixedly connected to the mold through the fixing holes and fixing bolts.

8. The insert for core pulling in a mold as described in claim 1, characterized in that, The thickness of the pry block is 0.1-0.5mm less than the width of the groove.

9. A mold, comprising a moving mold and a fixed mold, characterized in that, The mold core-pulling insert as described in any one of claims 1-8 is provided inside the fixed mold.

10. A method for operating the mold according to claim 9, characterized in that, Includes the following steps: The moving mold moves toward the fixed mold in the first direction. After the parting surface of the moving mold contacts the top surface of the guide block, it drives the guide block to move until the parting surface of the moving mold contacts the top surface of the insert body, thus completing the mold closing. During the movement of the guide block, the push block at the bottom of the guide block cooperates with the groove surface of the core-pulling body groove. The movement of the guide block causes the core-pulling body to move in the second direction, and the molding structure extends to the outside of the insert body. Injection molding of injection molded products; After the injection molding of the product is completed, the moving mold moves away from the fixed mold, and at the same time the guide block also moves away from the second channel. With the cooperation of the push block and the groove surface, the core pulling body moves along the second direction, and the molding structure retracts into the second channel. Eject the injection molded product from the fixed mold.

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