A precision injection mold for multi-undercut plastic parts

Abstract

This utility model discloses a precision injection mold for multi-undercut plastic parts, belonging to the field of injection mold technology. It includes an upper mold plate and a lower mold plate. A fixed external molding mechanism for molding the outer walls of the first and second tube sections of the plastic part is installed between the upper and lower mold plates. A movable internal molding mechanism is also installed between the upper and lower mold plates. The movable internal molding mechanism includes a first internal molding component, a second internal molding component, a slanted ejector molding component, and a second linkage drive component. Through this method, after injection molding, the upper and lower mold plates gradually separate. The first internal molding component is the first to be extracted and reset from the plastic part, causing the slanted ejector molding component to reset synchronously. Subsequently, the second internal molding component is extracted from the other side of the plastic part. Finally, the fixed external molding mechanism separates, achieving step-by-step demolding of the plastic part. This effectively reduces the deformation problems that easily occur during traditional one-time demolding, effectively improving production efficiency and product quality.

Description

Technical Field

[0001] This utility model relates to the field of injection mold technology, specifically to a precision injection mold for multi-undercut plastic parts. Background Technology

[0002] An injection mold is a precision production tool used in the injection molding process to give plastic a specific shape and size.

[0003] An existing injection molded product is shown in the attached diagram of the instruction manual. Figure 1 As shown, the plastic part 7 is mainly composed of a first tube section 71 with a relatively small diameter and a second tube section 72 with a relatively large diameter. The first tube section 71 and the second tube section 72 are coaxially arranged. The outer periphery of the first tube section 71 is evenly provided with a number of slots 73. The outer end of the second tube section 72 has a number of undercuts 74. Due to the long overall length, the core block will have a large contact area with the product, which will cause the plastic part 7 to be pulled and deformed. In addition, the undercuts 74 will also cause demolding difficulties.

[0004] Based on this, this utility model designs a precision injection mold for multi-inverted plastic parts to solve the above problems. Utility Model Content

[0005] In view of the above-mentioned shortcomings of the existing technology, the present invention provides a precision injection mold for multi-undercut plastic parts.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A precision injection mold for multi-undercut plastic parts includes an upper mold plate and a lower mold plate;

[0008] A fixed external molding mechanism for molding the outer walls of the first and second tube sections of the plastic part is installed between the upper and lower mold plates. A movable internal molding mechanism is also installed between the upper and lower mold plates. The movable internal molding mechanism includes a first internal molding component, a second internal molding component, a slanted ejector molding component, and a second linkage drive component. The first and second internal molding components are respectively installed on the left and right sides of the fixed external molding mechanism through the second linkage drive component. The second linkage drive component is used to control the first and second internal molding components to synchronously enter and exit the first and second tube sections of the plastic part along the axial direction of the plastic part to form their inner walls when the upper and lower mold plates are opening and closing. Furthermore, a slanted ejector molding component is also installed on the second internal molding component. The slanted ejector molding component is used to form an inverted inner support after being pushed by the first tube section.

[0009] Furthermore, the fixed external forming mechanism includes an upper forming block, a lower forming block, a side forming block, and a first linkage drive assembly. The upper forming block is fixedly installed at the lower end of the upper template, the lower forming block is fixedly installed at the upper end of the lower template, and two first linkage drive assemblies are symmetrically installed on the front and rear sides of the lower forming block. The side forming block is installed on the first linkage drive assembly.

[0010] Furthermore, the first linkage drive component includes an upper push plate, a lower sliding pin, and a sliding seat. The sliding seat is fixedly installed on the lower template, and the side forming block is slidably connected to the sliding seat. The lower sliding pin is fixedly installed on the side of the side forming block. An upper push plate is fixedly installed at the lower end of the upper template, and a sliding groove is provided on the upper push plate to be slidably connected to the lower sliding pin.

[0011] Furthermore, the first internal molding component includes a first core block and a first stop block. One end of the first stop block is connected to the second linkage drive component, and the other end of the first stop block is fixedly installed with a first core block that mates with the inner wall of the first tube of the plastic part.

[0012] Furthermore, the second internal molding component includes a second core block, a third core block, and a second stop block. One end of the second stop block is connected to the second linkage drive component, and the other end of the second stop block is fixedly installed with a third core block that mates with the inner wall of the second tube of the plastic part. The end of the third core block away from the second stop block is fixedly installed with a second core block that mates with the inner wall of the first tube of the plastic part.

[0013] Furthermore, the inclined top forming assembly includes a support block, a push block, a spring, and a push rod. The support block is slidably connected to the third core block, and multiple support blocks are provided, each corresponding to an inverted buckle. The second core block has a receiving groove that is slidably connected to the push block. A matching inclined surface is provided between the push block and the support block, and the push block and the support block are slidably connected by a limiting structure. A push rod is fixedly installed at the end of the push block away from the support block, and the push rod is slidably connected to the second core block. The spring is located in the receiving groove and sleeved on the outside of the push rod, with both ends of the spring abutting against the push block and the second core block, respectively.

[0014] Furthermore, the second linkage drive assembly includes an upper inclined insert rod, a lower sliding block, a sliding rod, and a fixed seat. The fixed seat is fixedly installed on the upper end of the lower template. The sliding rod is slidably connected to the fixed seat. One end of the sliding rod near the lower forming block is fixedly connected to the first core block or the third core block. The other end of the sliding rod is fixedly installed with the lower sliding block. The upper end of the upper inclined insert rod is fixedly connected to the upper template. The lower sliding block has a sliding inclined slot that cooperates with the upper inclined insert rod.

[0015] Furthermore, protrusions for forming grooves are fixedly installed on the upper forming block, lower forming block, and side forming block.

[0016] Compared with the prior art, the advantages of this utility model are as follows: During the mold closing process of the upper and lower mold plates, the fixed outer molding mechanism is started first. After the fixed outer molding mechanism is fully formed into the molding cavity for molding the outer wall of the plastic part, the second linkage drive component on one side first drives the second inner molding component to move inward to the fixed outer molding mechanism. After the second inner molding component is in place, the second linkage drive component on the other side drives the first inner molding component to move inward to the fixed outer molding mechanism until the first inner molding component and the second inner molding component abut against each other. Then the first inner molding component pushes the inclined ejector molding component to extend. After the upper and lower mold plates are fully closed, the first inner molding component, the second inner molding component and the inclined ejector molding component form the core block for molding the inner wall of the plastic part. Thus, the injection molding operation of the plastic part is completed through the cooperation of the molding cavity and the core block.

[0017] After injection molding is completed, the upper and lower mold plates gradually separate. The first inner molding component is pulled out and reset first from the plastic part, so that the inclined ejector molding component is also reset at the same time. Then the second inner molding component is pulled out from the other side of the plastic part. Finally, the fixed outer molding mechanism separates, realizing the step-by-step demolding of the plastic part. This effectively reduces the deformation problem that is easy to occur when demolding in a traditional one-time demolding, and effectively improves production efficiency and product quality. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a three-dimensional structural diagram of the plastic part;

[0020] Figure 2 This utility model relates to a three-dimensional precision injection mold for multi-undercut plastic parts. Figure 1 ;

[0021] Figure 3 This is a front sectional view of a precision injection mold for multi-inverted plastic parts according to the present invention;

[0022] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0023] Figure 5 This utility model relates to a three-dimensional precision injection mold for multi-undercut plastic parts. Figure 2 ;

[0024] Figure 6 This utility model relates to a three-dimensional precision injection mold for multi-undercut plastic parts. Figure 3 ;

[0025] Figure 7 This utility model relates to a three-dimensional precision injection mold for multi-undercut plastic parts. Figure 4 .

[0026] The labels in the diagram represent:

[0027] 1. Upper template; 2. Lower template; 3. Fixed external molding mechanism; 31. Upper molding block; 32. Lower molding block; 33. Side molding block; 4. First linkage drive assembly; 41. Upper push plate; 42. Lower sliding pin; 43. Sliding groove; 44. Sliding seat; 5. Second linkage drive assembly; 51. Upper inclined insert rod; 52. Lower sliding block; 53. Inclined slot; 54. Sliding rod; 55. Fixed seat; 6. Movable internal molding mechanism; 61. First core block; 62. First stop block; 63. Second core block; 64. Third core block; 65. Second stop block; 66. Support block; 67. Push block; 68. Spring; 69. Push rod; 7. Plastic part; 71. First tube section; 72. Second tube section; 73. Groove; 74. Undercut. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0029] The terms "left," "right," "front," "back," "up," and "down" used in the following description refer to the orientation from the perspective of the front view.

[0030] In some embodiments, please refer to the accompanying drawings. Figures 1-7 A precision injection mold for multi-inverted plastic parts, comprising an upper mold plate 1 and a lower mold plate 2;

[0031] A fixed external molding mechanism 3 for molding the outer walls of the first tube 71 and the second tube 72 of the plastic part 7 is installed between the upper mold plate 1 and the lower mold plate 2. A movable internal molding mechanism 6 is also installed between the upper mold plate 1 and the lower mold plate 2. The movable internal molding mechanism 6 includes a first internal molding component, a second internal molding component, a slanted ejector molding component, and a second linkage drive component 5. The first internal molding component and the second internal molding component are respectively installed on the left and right sides of the fixed external molding mechanism 3 through the second linkage drive component 5. The second linkage drive component 5 is used to control the first internal molding component and the second internal molding component to synchronously enter and exit the first tube 71 and the second tube 72 of the plastic part 7 along the axial direction of the plastic part 7 when the upper mold plate 1 and the lower mold plate 2 are opening and closing to form the inner walls of the two. Furthermore, a slanted ejector molding component is also installed on the second internal molding component. The slanted ejector molding component is used to form the inner support of the inverted buckle 74 after being pushed by the first tube 71.

[0032] In this utility model, during the mold closing process of the upper mold 1 and the lower mold 2, the fixed external molding mechanism 3 is started first. After the fixed external molding mechanism 3 completely forms the molding cavity for molding the outer wall of the plastic part 7, the second linkage drive component 5 on one side first drives the second internal molding component to move inward to the fixed external molding mechanism 3. After the second internal molding component is in place, the second linkage drive component 5 on the other side drives the first internal molding component to move inward to the fixed external molding mechanism 3 until the first internal molding component and the second internal molding component abut against each other. Then the first internal molding component pushes the inclined ejector molding component to extend, so that after the upper mold 1 and the lower mold 2 are completely closed, the first internal molding component, the second internal molding component and the inclined ejector molding component form the core block for molding the inner wall of the plastic part 7. Thus, the injection molding operation of the plastic part 7 is completed through the cooperation of the molding cavity and the core block.

[0033] After injection molding is completed, the upper mold plate 1 and the lower mold plate 2 gradually separate. The first inner molding component is first pulled out and reset from the plastic part 7, so that the inclined ejector molding component is also reset at the same time. Then the second inner molding component is pulled out from the other side of the plastic part 7. Finally, the fixed outer molding mechanism 3 separates, realizing the step-by-step demolding of the plastic part 7, thereby effectively reducing the deformation problem that is easy to occur during traditional one-time demolding, and effectively improving production efficiency and product quality.

[0034] The fixed external forming mechanism 3 includes an upper forming block 31, a lower forming block 32, a side forming block 33, and a first linkage drive assembly 4. The upper forming block 31 is fixedly installed at the lower end of the upper template 1, and the lower forming block 32 is fixedly installed at the upper end of the lower template 2. The two first linkage drive assemblies 4 are symmetrically installed on the front and rear sides of the lower forming block 32. The side forming block 33 is installed on the first linkage drive assembly 4. The upper forming block 31, the lower forming block 32, and the side forming block 33 are all fixedly installed with protrusions for forming grooves 73.

[0035] The first linkage drive component 4 includes an upper push plate 41, a lower sliding pin 42, and a sliding seat 44. The sliding seat 44 is fixedly installed on the lower template 2, and the side forming block 33 is slidably connected to the sliding seat 44. The lower sliding pin 42 is fixedly installed on the side of the side forming block 33. The upper push plate 41 is fixedly installed at the lower end of the upper template 1, and the upper push plate 41 has a sliding groove 43 that is slidably connected to the lower sliding pin 42.

[0036] In this embodiment, the sliding groove 43 is composed of an inclined groove and the binding grooves at both ends of the inclined groove. During the mold closing process of the upper mold plate 1 and the lower mold plate 2, when the lower sliding pin 42 slides in the inclined groove on the upper push plate 41, the side forming block 33 can slide along the sliding seat 44; when the lower sliding pin 42 slides in the vertical groove on the upper push plate 41, the position of the side forming block 33 remains locked.

[0037] The first internal molding component includes a first core block 61 and a first stop block 62. One end of the first stop block 62 is connected to the second linkage drive component 5, and the other end of the first stop block 62 is fixedly installed with the first core block 61 that cooperates with the inner wall of the first tube 71 of the plastic part 7.

[0038] The second internal molding assembly includes a second core block 63, a third core block 64, and a second stop block 65. One end of the second stop block 65 is connected to the second linkage drive assembly 5, and the other end of the second stop block 65 is fixedly installed with a third core block 64 that mates with the inner wall of the second tube 72 of the plastic part 7. The end of the third core block 64 away from the second stop block 65 is fixedly installed with a second core block 63 that mates with the inner wall of the first tube 71 of the plastic part 7.

[0039] The inclined top forming assembly includes a support block 66, a push block 67, a spring 68, and a push rod 69. The support block 66 is slidably connected to the third core block 64, and multiple support blocks 66 are provided, each corresponding to an inverted buckle 74. The second core block 63 has a receiving groove that is slidably connected to the push block 67. A matching inclined surface is provided between the push block 67 and the support block 66, and the push block 67 and the support block 66 are slidably connected by a limiting structure. In this invention, the limiting structure adopts a dovetail groove and a dovetail block limiting structure. The push rod 69 is fixedly installed at the end of the push block 67 away from the support block 66, and the push rod 69 is slidably connected to the second core block 63. The spring 68 is located in the receiving groove and sleeved on the outside of the push rod 69. The two ends of the spring 68 abut against the push block 67 and the second core block 63, respectively. In the natural state of the spring 68, the push rod 69 extends from the receiving groove to the outside of the second core block 63.

[0040] The second linkage drive assembly 5 includes an upper inclined insert rod 51, a lower sliding block 52, a sliding rod 54, and a fixed seat 55. The fixed seat 55 is fixedly installed on the upper end of the lower template 2. The sliding rod 54 is slidably connected to the fixed seat 55. One end of the sliding rod 54 near the lower forming block 32 is fixedly connected to the first core block 61 or the third core block 64. The other end of the sliding rod 54 is fixedly installed with the lower sliding block 52. The upper end of the upper inclined insert rod 51 is fixedly connected to the upper template 1. The lower sliding block 52 has a sliding inclined slot 53 that cooperates with the upper inclined insert rod 51.

[0041] In this invention, during the mold closing process of the upper mold plate 1 and the lower mold plate 2, the upper molding block 31, the lower molding block 32, and the two side molding blocks 33 gradually approach each other to form a molding cavity for molding the outer wall of the plastic part 7. Then, the upper inclined insert 51 is inserted into the inclined slot 53 of the lower sliding block 52, causing the sliding rod 54 to slide downwards towards the lower molding block 32 under the limiting action of the fixed seat 55. The second core block 63 and the third core block 64 extend into the molding cavity until the second stop block 65 closes the molding cavity. After one side opening is blocked, the first stop block 62 extends into the cavity from the other side and gradually pushes the push rod 69 into the first stop block 62. Then, the push block 67 pushes the support block 66. When the first core block 61 and the second core block 63 abut against each other, the support block 66 extends completely. The first core block 61, the second core block 63, the third core block 64 and the support block 66 cooperate to form the core block for molding the inner wall of the plastic part 7. Thus, the molding operation of the plastic part 7 is realized through the cooperation of the molding cavity and the core block.

[0042] After the plastic part 7 is formed, the upper mold plate 1 and the lower mold plate 2 gradually separate. The first core block 61 is first pulled out from the plastic part 7. Under the reset action of the spring 68, the support block 66 retracts into the third core block 64. Then, the second core block 63 and the third core block 64 are pulled out from the other side of the plastic part 7. The core design with the two sides separated reduces the contact area between the core and the inner wall of the plastic part 7, reducing the possibility of tearing the finished injection molded part. Finally, the upper molding block 31, the lower molding block 32 and the side molding block 33 move away from each other, thereby realizing the step-by-step demolding operation of the plastic part 7.

[0043] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A precision injection mold for multi-undercut plastic parts, comprising an upper mold plate (1) and a lower mold plate (2), characterized in that: A fixed external molding mechanism (3) for molding the outer walls of the first tube (71) and the second tube (72) of the plastic part (7) is installed between the upper template (1) and the lower template (2). A movable internal molding mechanism (6) is also installed between the upper template (1) and the lower template (2). The movable internal molding mechanism (6) includes a first internal molding component, a second internal molding component, a slanted top molding component, and a second linkage drive component (5). The first internal molding component and the second internal molding component are respectively installed on the left and right sides of the fixed external molding mechanism (3) through the second linkage drive component (5). The second linkage drive component (5) is used to control the first internal molding component and the second internal molding component to enter and exit the first tube (71) and the second tube (72) of the plastic part (7) synchronously along the axial direction of the plastic part (7) to form the inner walls of the two. A slanted top molding component is also installed on the second internal molding component. The slanted top molding component is used to form the inner support of the undercut (74) after being pushed by the first tube (71).

2. The precision injection mold for multi-undercut plastic parts according to claim 1, characterized in that, The fixed external forming mechanism (3) includes an upper forming block (31), a lower forming block (32), a side forming block (33), and a first linkage drive assembly (4). The upper forming block (31) is fixedly installed at the lower end of the upper template (1), the lower forming block (32) is fixedly installed at the upper end of the lower template (2), and the two first linkage drive assemblies (4) are symmetrically installed on the front and rear sides of the lower forming block (32). The side forming block (33) is installed on the first linkage drive assembly (4).

3. The precision injection mold for multi-undercut plastic parts according to claim 2, characterized in that, The first linkage drive component (4) includes an upper push plate (41), a lower sliding pin (42) and a sliding seat (44). The sliding seat (44) is fixedly installed on the lower template (2), and the side forming block (33) is limited and slidably connected to the sliding seat (44). The side of the side forming block (33) is fixedly installed with the lower sliding pin (42). The upper push plate (41) is fixedly installed at the lower end of the upper template (1), and the upper push plate (41) is provided with a sliding groove (43) that is limited and slidably connected to the lower sliding pin (42).

4. The precision injection mold for multi-undercut plastic parts according to claim 3, characterized in that, The first internal molding component includes a first core block (61) and a first stop block (62). One end of the first stop block (62) is connected to the second linkage drive component (5), and the other end of the first stop block (62) is fixedly installed with a first core block (61) that cooperates with the inner wall of the first tube (71) of the plastic part (7).

5. The precision injection mold for multi-undercut plastic parts according to claim 4, characterized in that, The second internal molding assembly includes a second core block (63), a third core block (64), and a second stop block (65). One end of the second stop block (65) is connected to the second linkage drive assembly (5), and the other end of the second stop block (65) is fixedly installed with a third core block (64) that mates with the inner wall of the second tube (72) of the plastic part (7). The end of the third core block (64) away from the second stop block (65) is fixedly installed with a second core block (63) that mates with the inner wall of the first tube (71) of the plastic part (7).

6. The precision injection mold for multi-undercut plastic parts according to claim 5, characterized in that, The inclined top forming assembly includes a support block (66), a push block (67), a spring (68), and a push rod (69). The support block (66) is slidably connected to the third core block (64). Multiple support blocks (66) are provided and correspond one-to-one with the buckles (74). The second core block (63) has a receiving groove that is slidably connected to the push block (67). The push block (67) and the support block (66) are provided with a matching inclined surface. The push block (67) and the support block (66) are slidably connected by a limiting structure. The push rod (69) is fixedly installed at the end of the push block (67) away from the support block (66). The push rod (69) is slidably connected to the second core block (63). The spring (68) is located in the receiving groove and sleeved on the outside of the push rod (69). The two ends of the spring (68) abut against the push block (67) and the second core block (63) respectively.

7. The precision injection mold for multi-undercut plastic parts according to claim 6, characterized in that, The second linkage drive assembly (5) includes an upper inclined insert rod (51), a lower sliding block (52), a sliding rod (54), and a fixed seat (55). The fixed seat (55) is fixedly installed on the upper end of the lower template (2). The sliding rod (54) is limited and slidably connected to the fixed seat (55). One end of the sliding rod (54) near the lower forming block (32) is fixedly connected to the first core block (61) or the third core block (64). The other end of the sliding rod (54) is fixedly installed with the lower sliding block (52). The upper end of the upper inclined insert rod (51) is fixedly connected to the upper template (1). The lower sliding block (52) has a sliding inclined slot (53) that cooperates with the upper inclined insert rod (51).

8. The precision injection mold for multi-undercut plastic parts according to claim 7, characterized in that, The upper forming block (31), the lower forming block (32) and the side forming block (33) are all fixedly installed with protrusions for forming grooves (73).

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