Core-pulling mold capable of guaranteeing resetting of ejector pin
By introducing a forced reset mechanism into the injection mold, the problem of mold damage caused by ejector spring failure was solved, and the accurate reset of the ejector pin and the reliability of the mold were improved.
Patent Information
- Application Number
- CN202423111951.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2034-12-17
AI Technical Summary
In existing injection molds, the springs of the ejector mechanism cannot accurately reset after their service life ends, causing the ejector pins to collide with mold components, resulting in mold damage and affecting production efficiency and costs.
A forced reset mechanism is adopted, including an ejector rod, a rocker rod, a guide block, a pusher block, and a displacement sensor. When the mold is closed, the ejector rod pushes the rocker rod to reset the ejector plate. After the displacement sensor detects that the core-pulling slider has been fully reset, it indicates that the core-pulling slider should return to its original position to avoid collision.
It achieves accurate reset of the ejector pin, avoids collision between the ejector pin and mold components, improves the reliability and production stability of the mold, and reduces the risk of mold damage.
Smart Images
Figure CN223918557U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of injection mold technology, and in particular to a core-pulling mold that ensures the reset of the ejector pin. Background Technology
[0002] Currently, injection mold manufacturing typically includes an ejector mechanism for ejecting the product. This mechanism consists of an ejector plate and ejector pins mounted on it. Normally, during mold release, the ejector pins push the ejector pins through the rear mold to eject the product, after which the ejector pins retract. Before mold closing, the ejector mechanism must be reset; otherwise, the ejector pins protruding from the rear mold will interfere with the front mold and sliding blocks, and may also collide with the returning core-pulling slider, causing mold damage.
[0003] In the existing technology, most injection molds use springs to reset the ejector pin mechanism. The springs are installed on the guide pins of the ejector plate. When the injection mold is demolded, the ejector plate moves upward to push the ejector pins out of the product. At this time, the springs contract. After demolding is completed, the springs rebound to automatically reset the ejector plate and the ejector pins.
[0004] However, in the actual production and use of injection molds, springs have a limited lifespan. After a certain number of uses, the spring's elasticity will fail, causing the ejector mechanism to fail to reset accurately. This will damage the mold, affect the production schedule, increase production costs, and reduce production efficiency. Utility Model Content
[0005] The purpose of this invention is to provide a core-pulling mold that ensures the reset of the ejector pin, aiming to solve or at least partially solve the shortcomings of the above-mentioned background technology. It has a simple structure, can ensure the forced reset of the ejector pin mechanism, avoid damage to the mold, and improve the reliability of the mold.
[0006] This utility model provides a core-pulling mold for ensuring ejector pin reset, including an upper mold, a lower mold, and an ejector mechanism. A cavity for molding a product is provided between the upper and lower molds. The ejector mechanism includes an ejector pin and an ejector plate. The ejector plate is movably disposed below the lower mold, and the ejector pin is mounted on the ejector plate. The ejector pin penetrates the lower mold and can protrude from the cavity. The lower mold is provided with a core-pulling mechanism, which includes a core-pulling slider. The core-pulling slider is slidably disposed on the lower mold and can protrude from the cavity to participate in product molding. A forced reset mechanism is provided on each of the opposite sides of the core-pulling mold for ensuring ejector pin reset. The forced reset mechanism includes an ejector rod, a rocker arm, a guide block, a push block, and a displacement sensor. The upper end of the ejector rod is mounted by fasteners. The upper mold has an ejector pin extending vertically downwards at its lower end. A guide block is installed in the lower mold to guide the ejector pin. A push block is installed on the ejector plate. A rocker arm is rotatably mounted in the lower mold, with its movable end abutting against the push block. A displacement sensor is used to detect the reset status of the ejector plate in real time. At least one positioning block is provided on the side of the ejector pin facing the upper mold. The upper mold has a positioning groove that mates with the positioning block, and the positioning block is installed in the positioning groove. When the mold is closed, the ejector pin moves downwards along the guide block and pushes the rocker arm. The rocker arm rotates to push the push block, thereby causing the ejector plate to move downwards and fully reset. When the displacement sensor detects that the ejector plate has fully reset, the displacement sensor sends a signal to the core-pulling mechanism to instruct the core-pulling slider to move inwards into the cavity.
[0007] Furthermore, the two forced reset mechanisms are arranged in a centrally symmetrical manner.
[0008] Furthermore, the core-pulling mold that ensures the ejector pin reset also includes a base plate, which is located below the ejector plate. A displacement sensor is located on the base plate and is used to detect the distance between the ejector plate and the base plate.
[0009] Furthermore, the two side walls of the ejector pin can abut against the guide block and the push block respectively. After the mold is closed, the side wall of the ejector pin that abuts against the push block abuts against the movable end of the swing rod.
[0010] Furthermore, a first chamfer structure is provided on the upper end of the side of the guide block that is in contact with the top rod.
[0011] Furthermore, the lower end of the ejector pin and the movable end of the rocker pin are respectively provided with a second chamfer structure and a third chamfer structure. When the mold is closed, the second chamfer structure and the third chamfer structure abut against each other.
[0012] Furthermore, the positioning block and the top rod are integrally formed.
[0013] Furthermore, the upper mold is recessed with a first groove for accommodating the ejector rod, the lower mold is recessed with a second groove for accommodating the guide block and a movable groove for accommodating the rotation of the rocker arm, the ejector plate is recessed with a third groove for accommodating the push block, and the bottom plate is recessed with a mounting groove for accommodating the displacement sensor.
[0014] Furthermore, the lower mold is recessed with a first clearance groove for avoiding the ejector rod, and the first clearance groove, the second groove, and the movable groove are connected in a manner; the ejector plate is recessed with a second clearance groove for avoiding the ejector rod, and the third groove is connected in a manner to the second clearance groove.
[0015] Furthermore, the positioning groove is located within the first groove.
[0016] This utility model provides a core-pulling mold that ensures ejector pin reset. Through the cooperation of ejector rod, rocker rod, guide block, and push block, the core-pulling mold that ensures ejector pin reset can drive the ejector plate to force reset during the mold closing process, avoiding collision between the ejector pin and other parts of the mold, improving the reliability of the mold, and ensuring stable production. Through the cooperation of ejector plate and displacement sensor, the core-pulling slider only returns to its original position after the ejector plate is fully reset and the ejector pin is fully withdrawn from the cavity, avoiding collision between the core-pulling slider and the ejector pin that could cause mold damage. This provides a second layer of protection against mold damage and improves the reliability of the mold. By setting a positioning block on the ejector rod, the ejector rod directly bears the force when it abuts the rocker rod, without needing to bear the force through fasteners, avoiding the risk of fastener breakage and improving the reliability of the mold. In addition, the positioning block plays a positioning role, enabling the ejector rod to be quickly and accurately installed on the upper mold. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of a core-pulling mold for ensuring ejector pin reset in the mold-opening state according to Embodiment 1 of this utility model.
[0018] Figure 2 This is a cross-sectional view of a core-pulling mold for ensuring ejector pin reset in the mold-opening state according to Embodiment 1 of this utility model.
[0019] Figure 3 for Figure 1 A magnified diagram of point A in the middle.
[0020] Figure 4 for Figure 1 The diagram shows a pendulum rod.
[0021] Figure 5 This is a schematic diagram of a core-pulling mold for ensuring ejector pin reset after mold closing, according to Embodiment 1 of this utility model.
[0022] Figure 6 This is a cross-sectional view of a core-pulling mold after mold closing, which ensures the reset of the ejector pin according to Embodiment 1 of this utility model.
[0023] Figure 7 For along Figure 5 A partial cross-sectional view of the middle BB line.
[0024] Figure 8This is a schematic diagram of an omitted forced reset mechanism for a core-pulling mold after mold closing, which ensures the reset of the ejector pin according to Embodiment 2 of this utility model. Detailed Implementation
[0025] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.
[0026] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and claims of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.
[0027] The directional terms such as "up," "down," "left," "right," "front," "back," "top," and "bottom" (if present) used in the specification and claims of this utility model are defined according to the position of the structures in the drawings and the relative positions of the structures, and are only for the purpose of clarity and convenience in expressing the technical solution. It should be understood that the use of directional terms should not limit the scope of protection claimed in this application.
[0028] Example 1:
[0029] Please see Figure 1 , Figure 2 and Figures 4-7 A core-pulling mold for ensuring ejector pin reset includes an upper mold 10, a lower mold 20, and an ejector mechanism 40. A cavity 100 for molding a product is provided between the upper mold 10 and the lower mold 20. The ejector mechanism 40 includes an ejector pin 41 and an ejector plate 42. The ejector plate 42 is movably disposed below the lower mold 20. The ejector pin 41 is mounted on the ejector plate 42, penetrates the lower mold 20, and can protrude from the cavity 100. The lower mold 20 is provided with a core-pulling mechanism 50, which includes a core-pulling slider 51. The core-pulling slider 51 is slidably disposed on the lower mold 20 and can protrude from the cavity 100 to participate in product molding.
[0030] A forced reset mechanism 60 is provided on each of the opposite sides of the core-pulling mold that ensures the reset of the ejector pin. Each forced reset mechanism 60 includes an ejector rod 61, a rocker rod 62, a guide block 63, a push block 64, and a displacement sensor 65. The upper end of the ejector rod 61 is mounted on the upper mold 10 by a fastener 70, and the lower end of the ejector rod 61 extends vertically downward. The guide block 63 is mounted on the lower mold 20 and is used to guide the ejector rod 61. The push block 64 is mounted on the ejector plate 42. The rocker rod 62 is rotatably mounted on the lower mold 20, and the movable end 621 of the rocker rod 62 abuts against the push block 64. The displacement sensor 65 is used to detect the reset status of the ejector plate 42 in real time.
[0031] At least one positioning block 611 is provided on the side of the push rod 61 facing the upper mold 10. The upper mold 10 is recessed with a positioning groove 11 that cooperates with the positioning block 611. The positioning block 611 is installed in the positioning groove 11.
[0032] When the mold is closed, the ejector pin 61 moves downward along the guide block 63 and pushes the rocker arm 62. The rocker arm 62 rotates to push the push block 64, thereby driving the ejector plate 42 to move downward and fully reset. When the displacement sensor 65 detects that the ejector plate 42 is fully reset, the displacement sensor 65 sends a signal to the core pulling mechanism 50 to instruct the core pulling slider 51 to move inward to the cavity 100.
[0033] More specifically, the core-pulling slider 51 is driven by a driving device 52, which can drive the core-pulling slider 51 to reciprocate on the lower mold 20. The driving device 52 is electrically connected to the displacement sensor 65.
[0034] The core-pulling mold for ensuring ejector pin reset provided in this embodiment, through the cooperation of ejector rod 61, rocker rod 62, guide block 63, and push block 64, enables the ejector plate 42 to be forcibly reset during mold closing, avoiding collision between ejector pin 41 and other parts of the mold, improving mold reliability, and ensuring stable production. Through the cooperation of ejector plate 42 and displacement sensor 65, the core-pulling slider 51 only returns to its original position after the ejector plate 42 is fully reset and the ejector pin 41 has completely withdrawn from the cavity 100, avoiding collision between the core-pulling slider 51 and ejector pin 41 that could damage the mold, providing a second layer of protection against mold damage and improving mold reliability. By setting a positioning block 611 on ejector rod 61, the ejector rod 61 is directly stressed when it abuts against rocker rod 62, rather than being stressed through fastener 70, avoiding the risk of fastener 70 breakage and improving mold reliability. In addition, the positioning block 611 plays a positioning role, enabling the ejector rod 61 to be quickly and accurately installed on the upper mold 10.
[0035] In this embodiment, the two forced reset mechanisms 60 are arranged symmetrically on the center. By symmetrically positioning the two forced reset mechanisms 60 on opposite sides of the core-pulling mold that ensures ejector pin reset, the ejector plate 42 can move downwards smoothly during the reset process, preventing damage to the ejector pin 41 due to imbalance during downward movement of the ejector plate 42, thus avoiding mold damage.
[0036] Please see Figure 1 and Figure 5The core-pulling mold that ensures ejector pin reset also includes a base plate 30, which is located below the ejector plate 42. A displacement sensor 65 is mounted on the base plate 30 and is used to detect the distance between the ejector plate 42 and the base plate 30. During mold closing, when the displacement sensor 65 detects that the distance between the ejector plate 42 and the base plate 30 reaches a preset value, the displacement sensor 65 sends a signal to the core-pulling mechanism 50 to instruct the drive device 52 to drive the core-pulling slider 51 to move inward.
[0037] In this embodiment, the forced reset mechanism 60 is externally mounted on the core-pulling mold that ensures the reset of the ejector pin. More specifically, the ejector rod 61 is mounted on the side wall surface of the upper mold 10, the guide block 63 and the swing rod 62 are respectively mounted on the side wall surface of the lower mold 20, and the push block 64 is mounted on the side wall surface of the ejector plate 42.
[0038] The two side walls of the ejector pin 61 can abut against the guide block 63 and the push block 64 respectively. After the mold is closed, the side wall of the ejector pin 61 that abuts against the push block 64 abuts against the movable end 621 of the rocker arm 62. The guide block 63 can guide the ejector pin 61 to accurately abut against the movable end 621 of the rocker arm 62.
[0039] Furthermore, the distance between the guide block 63 and the push block 64 in the left-right direction is greater than the length of the push rod 61 in the left-right direction. This arrangement allows the push block 64 to avoid the push rod 61.
[0040] Please see Figure 1 and Figure 2 The core-pulling mold that ensures the ejector pin reset is in the open state: the ejector pin 61 is located above the guide block 63 and the rocker arm 62, the ejector pin 41 is in the ejection state, the push block 64 is abutting below the rocker arm 62, and the movable end 621 of the rocker arm 62 is located directly below the ejector pin 61.
[0041] Please see Figure 5 and Figure 6 When the core-pulling mold for ensuring ejector pin reset is closed: ejector rod 61 moves downward with upper mold 10, one side wall of ejector rod 61 is in contact with the side wall of guide block 63, the lower end of ejector rod 61 abuts against and pushes movable end 621, movable end 621 rotates around the fixed end of rocker rod 62 and moves downward, movable end 621 pushes push block 64 downward, push block 64 drives ejector plate 42 to move downward, thereby causing ejector pin 41 to move downward; when movable end 621 is in contact with the other side wall of ejector rod 61, ejector plate 42 completes reset and stops moving. When displacement sensor 65 detects that the distance between ejector plate 42 and base plate 30 reaches a preset value, displacement sensor 65 sends a signal to core-pulling mechanism 50 to instruct drive device 52 to drive core-pulling slider 51 to return to its original position.
[0042] Please see Figures 3-4The upper end of the side of the guide block 63 that is in contact with the ejector pin 61 is provided with a first chamfer structure 631. The first chamfer structure 631 can improve the guiding effect of the guide block 63 on the ejector pin 61, and at the same time prevent the ejector pin 61 from colliding with the guide block 63 and causing damage to the mold. When the mold is closed, the ejector pin 61 can move downward more smoothly under the guidance of the guide block 63 through the first chamfer structure 631, so that the side wall of the ejector pin 61 is in contact with the side wall of the guide block 63.
[0043] More specifically, the first chamfer structure 631 can be either a bevel or a rounded corner. In this embodiment, the first chamfer structure 631 is a bevel.
[0044] The lower end of the ejector pin 61 and the movable end 621 of the rocker arm 62 are respectively provided with a second chamfer structure 612 and a third chamfer structure 623. During mold closing, the second chamfer structure 612 and the third chamfer structure 623 abut against each other, which allows the ejector pin 61 to push the rocker arm 62 more smoothly. In addition, the second chamfer structure 612 and the third chamfer structure 623 can reduce the wear rate of the ejector pin 61 and the rocker arm 62, respectively, and improve their durability.
[0045] More specifically, the second chamfer structure 612 can be a bevel or a rounded corner. In this embodiment, the second chamfer structure 612 is a rounded corner. The third chamfer structure 623 can be a bevel or a rounded corner. In this embodiment, the third chamfer structure 623 is a rounded corner.
[0046] Please see Figure 7 The positioning block 611 and the ejector pin 61 are integrally formed. This is beneficial because when the ejector pin 61 abuts against the rocker arm 62, the ejector pin 61 is directly subjected to force through the positioning block 611, rather than through the fastener 70. Since the fastener 70 is more prone to breakage, this avoids the risk of the fastener 70 breaking and improves the reliability of the mold.
[0047] Example 2:
[0048] A core-pulling mold for ensuring ejector pin reset has a structure similar to that of the core-pulling mold for ensuring ejector pin reset in Embodiment 1, except that:
[0049] Please see Figure 8 The forced reset mechanism 60 is installed in a built-in manner on the core-pulling mold that ensures the reset of the ejector pin.
[0050] The upper mold 10 has a first recess 12 for accommodating the ejector pin 61, the lower mold 20 has a second recess 21 for accommodating the guide block 63 and a movable groove 22 for accommodating the rotation of the rocker arm 62, the ejector plate 42 has a third recess 421 for accommodating the push block 64, and the base plate 30 has a mounting groove 31 for accommodating the displacement sensor 65. This design reduces the size of the mold and allows for more flexible mold arrangement.
[0051] Furthermore, the lower mold 20 is recessed with a first clearance groove 23 for avoiding the ejector pin 61, and the first clearance groove 23, the second groove 21, and the movable groove 22 are connected; the ejector plate 42 is recessed with a second clearance groove 422 for avoiding the ejector pin 61, and the third groove 421 is connected to the second clearance groove 422. In addition, the base plate 30 is recessed with a third clearance groove 32 for avoiding the ejector pin 61.
[0052] More specifically, the positioning groove 11 is located within the first groove 12.
[0053] The advantages of the core-pulling mold with guaranteed ejector pin reset provided by this utility model include:
[0054] (1) Simple structure.
[0055] (2) It can drive the ejector plate 42 and ejector 41 to perform forced reset, avoid the ejector 41 from colliding with other parts of the mold, improve the reliability of the mold, and ensure stable production.
[0056] (3) It can detect the reset status of the ejector plate 42 in real time, providing a second layer of protection to prevent mold damage.
[0057] (4) The two forced reset mechanisms 60 are arranged in a centrally symmetrical manner, which can ensure that the forced reset of the ejector mechanism 40 is carried out smoothly.
[0058] (5) The forced reset mechanism 60 is built-in, which can reduce the volume of the mold and make the mold arrangement more flexible.
[0059] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.
Claims
1. A core-pulling mold with a guarantee of ejector pin reset, comprising an upper mold (10), a lower mold (20) and an ejector pin mechanism (40), a cavity (100) for forming a product is arranged between the upper mold (10) and the lower mold (20), the ejector pin mechanism (40) comprises an ejector pin (41) and an ejector pin plate (42), the ejector pin plate (42) is movably arranged below the lower mold (20), the ejector pin (41) is mounted on the ejector pin plate (42), the ejector pin (41) penetrates through the lower mold (20) and can protrude into the cavity (100), the lower mold (20) is provided with a core-pulling mechanism (50), the core-pulling mechanism (50) comprises a core-pulling slider (51), the core-pulling slider (51) is slidably arranged on the lower mold (20) and can protrude into the cavity (100) and participate in the forming of the product, characterized in that, The relative two sides of the core-pulling mold are respectively provided with a forced reset mechanism (60), each of the forced reset mechanism (60) comprises a ejector rod (61), a swing lever (62), a guide block (63), a push block (64) and a displacement sensor (65), the upper end of the ejector rod (61) is installed on the upper die (10) through a fastener (70), and the lower end of the ejector rod (61) extends vertically downward, the guide block (63) is installed on the lower die (20) and used for guiding the ejector rod (61), the push block (64) is installed on the ejector rod plate (42), the swing lever (62) is rotationally arranged on the lower die (20), and the movable end (621) of the swing lever (62) abuts against the push block (64), the displacement sensor (65) is used for detecting the reset condition of the ejector rod plate (42) in real time, one side of the ejector rod (61) towards the upper die (10) is provided with at least one positioning block (611), and the upper die (10) is concavely provided with a positioning groove (11) matched with the positioning block (611), the positioning block (611) is installed in the positioning groove (11). When the mold is closed, the ejector rod (61) moves downward along the guide block (63) and pushes the swing lever (62), the swing lever (62) rotates to push the push block (64) to drive the ejector rod plate (42) to move downward and completely reset; when the displacement sensor (65) detects that the ejector rod plate (42) is completely reset, the displacement sensor (65) sends a signal to the core-pulling mechanism (50) to indicate that the core-pulling slider (51) moves inward to the cavity (100).
2. The core back guaranteeing draw mold according to claim 1, wherein, The two forced reset mechanisms (60) are arranged in a central symmetry.
3. The core back guaranteeing draw mold according to claim 1, wherein, The core-pulling mold for ensuring the reset of the ejector rod further comprises a bottom plate (30), the bottom plate (30) is arranged below the ejector rod plate (42), and the displacement sensor (65) is arranged on the bottom plate (30) and used for detecting the distance between the ejector rod plate (42) and the bottom plate (30).
4. The core back guaranteeing draw mold according to claim 1, wherein, The two side walls of the ejector rod (61) can abut against the guide block (63) and the push block (64) respectively, after the mold is closed, one side wall of the ejector rod (61) abutting against the swing lever (62) abuts against the movable end (621) of the swing lever (62).
5. The core back guaranteeing draw mold according to claim 4, wherein, The upper end of one side of the guide block (63) abutting against the ejector rod (61) is provided with a first chamfer structure (631).
6. The core back guaranteeing draw mold according to claim 1, wherein, The lower end of the ejector rod (61) and the movable end (621) of the swing lever (62) are respectively provided with a second chamfer structure (612) and a third chamfer structure (623), and the second chamfer structure (612) abuts against the third chamfer structure (623) when the mold is closed.
7. The core back guaranteeing draw mold according to claim 1, wherein, The positioning block (611) is integrally formed with the ejector rod (61).
8. The core back guaranteeing draw mold according to claim 3, wherein, The upper die (10) is concave with a first recess (12) for accommodating the ejector rod (61), the lower die (20) is concave with a second recess (21) for accommodating the guide block (63) and a movable slot (22) for accommodating the rotation of the swing lever (62) respectively, the ejector rod plate (42) is concave with a third recess (421) for accommodating the push block (64), and the bottom plate (30) is concave with a mounting slot (31) for accommodating the displacement sensor (65).
9. The core back guaranteeing draw mold according to claim 8, wherein, The lower die (20) is concave with a first avoiding slot (23) for avoiding the ejector rod (61), and the first avoiding slot (23), the second recess (21) and the movable slot (22) are arranged in communication; the ejector rod plate (42) is concave with a second avoiding slot (422) for avoiding the ejector rod (61), and the third recess (421) and the second avoiding slot (422) are arranged in communication.
10. The core back guaranteeing draw mold according to claim 8, wherein, The positioning slot (11) is located in the first recess (12).