A two-stage ejection and reset structure for the return needle
By employing a two-stage ejection and reset structure in the injection mold, the synchronous or disengaged movement of the ejector plate is achieved through the reset return pin and the ejection linkage, thus solving the problems of jamming and stuckness during the reset process of the ejector plate and improving the efficiency of injection molding production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHENGDU AEROSPACE MOLD & PLASTIC CO LTD
- Filing Date
- 2025-06-05
- Publication Date
- 2026-07-17
AI Technical Summary
In existing injection molds, the ejector plate is prone to jamming or getting stuck during the reset process, which affects the efficiency of injection molding production of parts.
The structure employs a two-stage ejection and reset mechanism. By setting a reset return needle and an ejection linkage between the first and second ejector panels, the push rod of the hydraulic cylinder drives the second ejector panel to move synchronously, and the reset return needle drives the first ejector panel to reset synchronously. The ejection linkage enables the first and second ejector panels to move synchronously or disengage at different strokes, thus avoiding jamming and stuck.
It effectively solves the problems of jamming and stuckness during the reset process of the ejector plate, improves the secondary ejection capability of the ejector sleeve in the narrow space inside the mold, and ensures the smooth progress of injection molding production.
Smart Images
Figure CN224510314U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the technical field of injection molds, specifically relating to a two-stage ejection and reset structure for a return pin. Background Technology
[0002] To install screw posts on injection-molded products, an ejector sleeve structure needs to be designed into the product beforehand. During the ejection process of the ejector sleeve after the part is formed, if the ejection radius of the mold is too large, the ejector sleeve will be ejected too high. This can lead to the ejector pin colliding with the inner wall step of the ejector sleeve during the subsequent reset process, causing the ejector pin to break or the ejector sleeve wall to crack. To avoid ejector sleeve damage, existing technologies often use a two-stage ejection structure to achieve segmented ejection of the ejector sleeve. That is, two sets of ejector pin plates are used to achieve secondary ejection of the ejector sleeve, thereby reducing the overall ejection stroke of the ejector sleeve.
[0003] However, due to the narrow internal space of the injection mold and the large volume of the connection structure between the two sets of ejector plates, the existing two sets of ejector plates are prone to jamming or even freezing during the reset linkage process, which prevents the ejector plate from resetting normally and seriously affects the production efficiency of injection molding of parts.
[0004] Therefore, in response to the aforementioned technical problems of the two sets of ejector plate structures, this utility model discloses a two-stage ejection and reset structure for the return needle. Utility Model Content
[0005] This utility model discloses a two-stage ejection reset structure for the return pin, which can solve the problem of reset jamming or even reset dead during the reset process of the ejector pin panel in injection molds.
[0006] This utility model is achieved through the following technical solution:
[0007] A two-stage ejection and reset structure includes a first ejector panel and a second ejector panel arranged in parallel. A reset return pin and an ejection linkage are provided between the first and second ejector panels. A hydraulic cylinder is arranged on the top of the second ejector panel parallel to the axial direction of the reset return pin. The reset return pin engages with the first ejector panel along the ejection direction of the hydraulic cylinder and slides with the first ejector panel along the retraction direction of the hydraulic cylinder. The ejection linkage engages with the first ejector panel during the first retraction stroke of the hydraulic cylinder, causing the first and second ejector panels to move synchronously. During the second retraction stroke, the ejection linkage disengages from the first ejector panel, causing the first ejector panel to no longer move with the second ejector panel.
[0008] When the push rod of the hydraulic cylinder is ejected, it corresponds to the mold reset process. The ejection of the push rod of the hydraulic cylinder drives the second ejector plate to move downward. At the same time, the reset return pin connected between the second ejector plate and the first ejector plate drives the first ejector plate to move downward synchronously to achieve synchronous forced reset.
[0009] When the cylinder push rod retracts, it corresponds to the ejection process of the mold. During the first stroke of the cylinder push rod retraction, the second ejector plate moves upward. At this time, the return pin and the first ejector plate are relatively slidably connected, and the ejection linkage is engaged with the first ejector plate, ensuring that the first and second ejector plates are ejected synchronously during the first stroke of the cylinder retraction. When the cylinder push rod completes the first stroke and continues to retract for the second stroke, the ejection linkage is limited by the mold and disengages from the first ejector plate. At this time, only the second ejector plate continues to be ejected under the action of the cylinder, while the first ejector plate remains stationary.
[0010] To better realize this utility model, the bottom end of the reset pin is fixedly connected to the second ejector plate, and a shoulder is provided at the middle position of the reset pin. The shoulder abuts against the top of the first ejector plate along the ejection direction of the oil cylinder.
[0011] To better realize this utility model, the top of the first ejector plate is provided with a countersunk hole, the shoulder of the reset pin passes through the countersunk hole, and a pad is provided between the end face of the shoulder and the countersunk hole.
[0012] To better realize this utility model, the bottom of the second ejector plate is provided with an inverted stepped hole, and the top of the second ejector plate is provided with a countersunk hole coaxially connected with the inverted stepped hole. A connecting screw extending into the hole is passed through the inverted stepped hole, and the bottom end of the reset pin extends into the countersunk hole and is fixedly connected with the connecting screw.
[0013] To better realize this utility model, the ejection linkage component further includes a connecting post, a limiting T-post, and a linkage slider. The linkage slider is slidably disposed on the top of the second ejector panel. The limiting T-post passes through the first ejector panel from top to bottom, and the bottom end of the limiting T-post is connected to one side of the linkage slider through a sloping surface sliding engagement. The connecting post is disposed at the bottom of the first ejector panel. The bottom end of the connecting post is provided with a slot for engaging with the linkage slider on the side near the linkage slider. An elastic element is provided on the side of the linkage slider away from the connecting post.
[0014] To better realize this utility model, the elastic element further includes a spring, a guide post, and a baffle. The baffle is disposed on the side of the linkage slider away from the connecting post. The guide post is disposed on the side of the baffle close to the linkage slider. One end of the guide post is engaged with the linkage slider and simultaneously connected to the bottom of the limiting T-post through a sloping sliding fit. A spring is disposed on the outside of the guide post between the baffle and the linkage slider.
[0015] To better realize this utility model, the bottom end of the limiting T-post is provided with a pressing slope on the side near the guide post, and the pressing slope abuts against one end of the guide post.
[0016] Compared with the prior art, this utility model has the following advantages and beneficial effects:
[0017] This invention features an ejector linkage between the first and second ejector panels. During the first stroke of the second ejector panel driven by the hydraulic cylinder, the ejector linkage engages with the first ejector panel, enabling synchronous ejection of both panels. During the second stroke, the ejector linkage disengages from the first ejector panel, preventing further ejection. This allows the invention to adapt to the narrow spaces within the mold for secondary ejection of the ejector sleeve. Simultaneously, during the sleeve's reset process, the reset pin drives the first and second ejector panels to reset synchronously, effectively reducing the complexity of the reset connection between them and preventing jamming or sticking during the reset process. Attached Figure Description
[0018] Figure 1 A three-dimensional schematic diagram of the resetting structure where the return needle pushes out twice;
[0019] Figure 2 This is a partial top view of the resetting structure where the return needle pushes out twice;
[0020] Figure 3 for Figure 2 Sectional view along axis AA;
[0021] Figure 4 for Figure 2 BB-direction sectional view;
[0022] Figure 5 This is a schematic diagram of the ejection linkage component.
[0023] Wherein: 1-First ejector panel; 2-Second ejector panel; 3-Reset return pin; 4-Ejection linkage component; 5-Oil cylinder; 6-Padded block; 41-Connecting column; 42-Limiting T-column; 43-Linkage slider; 44-Spring; 45-Guide column; 46-Baffle. Detailed Implementation Example 1:
[0024] This embodiment features a two-stage push-out reset structure for the return pin, such as... Figures 1-5 As shown, the device includes a first ejector panel 1 and a second ejector panel 2 arranged in parallel. A reset pin 3 and an ejector linkage 4 are provided between the first ejector panel 1 and the second ejector panel 2. A hydraulic cylinder 5 is arranged on the top of the second ejector panel 2 parallel to the axial direction of the reset pin 3. The reset pin 3 is engaged with the first ejector panel 1 along the ejection direction of the hydraulic cylinder 5, and the reset pin 3 is slidably connected to the first ejector panel 1 along the retraction direction of the hydraulic cylinder 5. The ejector linkage 4 engages with the first ejector panel 1 when the hydraulic cylinder 5 retracts for the first stroke, so that the first ejector panel 1 and the second ejector panel 2 move synchronously. The ejector linkage 4 disengages from the first ejector panel 1 when it retracts for the second stroke, so that the first ejector panel 1 no longer moves with the second ejector panel 2.
[0025] As shown in the figure, the process of the push rod of the hydraulic cylinder 5 pushing downward corresponds to the mold reset process. The push rod of the hydraulic cylinder 5 drives the second ejector plate 2 to move downward. At this time, the reset return pin 3 engages with the first ejector plate 1 along the downward ejection direction of the push rod of the hydraulic cylinder 5. Then, the reset return pin 3 drives the first ejector plate 1 to move downward synchronously with the second ejector plate 2 to achieve forced synchronous reset of the first ejector plate 1.
[0026] As shown in the figure, the upward retraction of the push rod of hydraulic cylinder 5 corresponds to the ejection process of the mold. The push rod of hydraulic cylinder 5 retracts in a first stroke followed by a second stroke. During the first stroke of the push rod retraction, the bottom end of the ejection linkage 4, located between the first ejector plate 1 and the second ejector plate 2, remains engaged with the first ejector plate 1, allowing the first ejector plate 1 to move synchronously with the second ejector plate 2. When the push rod of hydraulic cylinder 5 moves in the second stroke, the ejection linkage 4 is limited by the mold and disengages from the first ejector plate 1, preventing the first ejector plate 1 from continuing to move with the second ejector plate 2. At this point, only the second ejector plate 2 can continue to be ejected under the action of hydraulic cylinder 5. Example 2:
[0027] This embodiment is a further optimization based on Embodiment 1, such as... Figure 3 As shown, the bottom end of the reset pin 3 is fixedly connected to the second ejector plate 2, and a shoulder is provided at the middle position of the reset pin 3. The shoulder abuts against the top of the first ejector plate 1 along the ejection direction of the oil cylinder 5.
[0028] The reset pin 3 includes a large-diameter section and a small-diameter section, with a shoulder formed at the intersection of the two sections. The shoulder abuts against the first ejector plate 1 in the downward ejection direction of the hydraulic cylinder 5, while the small-diameter section of the reset pin 3 slides against the first ejector plate 1 in the upward retraction direction of the hydraulic cylinder 5. When the hydraulic cylinder 5 ejects downward, the shoulder abuts against the first ejector plate 1, causing the first ejector plate 1 and the second ejector plate 2 to move downward synchronously and reset. When the hydraulic cylinder 5 retracts upward, the small-diameter section of the reset pin 3 slides against the first ejector plate 1 in the upward retraction direction of the hydraulic cylinder 5, without affecting the movement of the ejection linkage 4 that drives the first ejector plate 1.
[0029] Furthermore, the top of the first ejector plate 1 is provided with a countersunk hole, and the shoulder of the return pin 3 passes through the countersunk hole, with a shim 6 provided between the end face of the shoulder and the countersunk hole. The shim 6 is fixedly installed inside the countersunk hole by connecting screws, and a connecting hole is provided at the center of the shim 6. The top end face of the shoulder and the connecting hole abuts against each other along the ejection direction of the hydraulic cylinder 5. By providing the shim 6, the fit clearance between the return pin 3 and the first ejector plate 1 can also be adjusted.
[0030] Furthermore, the bottom of the second ejector plate 2 is provided with an inverted stepped hole, and the top of the second ejector plate 2 is provided with a countersunk hole coaxially connected with the inverted stepped hole. A connecting screw extending into the hole is inserted in the inverted stepped hole, and the bottom end of the reset pin 3 extends into the countersunk hole and is provided with a threaded hole. The threaded hole is fixedly connected to the connecting screw.
[0031] The other parts of this embodiment are the same as those in Embodiment 1, so they will not be described again. Example 3:
[0032] This embodiment is a further optimization based on the above embodiment 1 or 2, such as... Figure 4 and Figure 5 As shown, the ejection linkage 4 includes a connecting post 41, a limiting T-post 42, and a linkage slider 43. The linkage slider 43 is slidably disposed on the top of the second ejector panel 2. The limiting T-post 42 passes through the first ejector panel 1 from top to bottom, and the bottom end of the limiting T-post 42 is connected to one side of the linkage slider 43 by a sloping sliding fit. The connecting post 41 is disposed at the bottom of the first ejector panel 1. The bottom end of the connecting post 41 is provided with a slot for engaging with the linkage slider 43 on the side close to the linkage slider 43. The side of the linkage slider 43 away from the connecting post 41 is provided with an elastic element.
[0033] The first ejector plate 1 has a through hole for the limiting T-post 42 to pass through. The T-shaped end of the limiting T-post 42 is located above the through hole, and the body of the limiting T-post 42 extends downward through the through hole. The bottom end of the limiting T-post 42 is connected to one side of the linkage slider 43 by a sloping sliding fit. During the first stroke of the retraction of the hydraulic cylinder 5, the bottom end of the limiting T-post 42 does not press against the linkage slider 43. At this time, under the elastic force of the elastic element, one end of the linkage slider 43 engages with the slot at the bottom of the connecting post 41, so that the first ejector plate 1 and the second ejector plate 2 can move synchronously. During the second stroke of the retraction of the hydraulic cylinder 5, the T-shaped end of the limiting T-post 42 contacts the mold and is limited by the mold, so that the limiting T-post 42 is stationary relative to the second ejector plate 2. When the second ejector plate 2 continues to move upward under the drive of the hydraulic cylinder 5, the bottom end of the limiting T-post 42 squeezes the linkage slider 43. At this time, the compression of the elastic element causes the linkage slider 43 to move away from the slot until the linkage slider 43 is dislodged from the slot. At this time, the first ejector plate 1 is separated from the second ejector plate 2 and cannot move upward synchronously with the second ejector plate 2.
[0034] The other parts of this embodiment are the same as those in Embodiment 1 or 2 above, so they will not be described again. Example 4:
[0035] This embodiment is a further optimization based on any one of embodiments 1-3 above, such as... Figure 4 and Figure 5 As shown, the elastic element includes a spring 44, a guide post 45, and a baffle 46. The baffle 46 is disposed on the side of the linkage slider 43 away from the connecting post 41. The guide post 45 is disposed on the side of the baffle 46 close to the linkage slider 43. One end of the guide post 45 is engaged with the linkage slider 43 and simultaneously connected to the bottom of the limiting T-post 42 through a sloping sliding engagement. A spring 44 is disposed on the outside of the guide post 45 between the baffle 46 and the linkage slider 43.
[0036] Furthermore, a pressing slope is provided on the bottom end of the limiting T-post 42 near the guide post 45, and the pressing slope abuts against one end of the guide post 45.
[0037] During the first stroke of the retraction of the hydraulic cylinder 5, the extrusion slope will not extrude the guide post 45. At this time, under the elastic force of the spring 44, the linkage slider 43 is engaged with the slot at the bottom of the connecting post 41, thereby enabling the first ejector plate 1 to move upward synchronously with the second ejector plate 2.
[0038] During the second stroke of the hydraulic cylinder 5 retraction, the top of the limiting T-post 42 cannot continue to move due to the mold limit. When the second ejector plate 2 continues to move upward, it will cause the extrusion slope to press the end of the guide post 45, causing the guide post 45 to drive the linkage slider 43 to move away from the slot until the linkage slider 43 disengages from the slot, thus completing the disengagement of the first ejector plate 1 and the second ejector plate 2. At this time, the first ejector plate 1 no longer moves upward synchronously with the second ejector plate 2.
[0039] The other parts of this embodiment are the same as any one of the embodiments 1-3 above, so they will not be described again.
[0040] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present utility model shall fall within the protection scope of the present utility model.
Claims
1. A double needle returning ejection reset structure, comprising a first needle panel (1) and a second needle panel (2) arranged in parallel, characterized in that, A reset pin (3) and an ejector linkage (4) are provided between the first ejector panel (1) and the second ejector panel (2). A hydraulic cylinder (5) is provided on the top of the second ejector panel (2) parallel to the axial direction of the reset pin (3). The reset pin (3) is engaged with the first ejector panel (1) along the ejection direction of the hydraulic cylinder (5). The reset pin (3) is slidably connected with the first ejector panel (1) along the retraction direction of the hydraulic cylinder (5). The ejector linkage (4) is engaged with the first ejector panel (1) when the hydraulic cylinder (5) retracts for the first stroke, so that the first ejector panel (1) and the second ejector panel (2) move synchronously. The ejector linkage (4) disengages from the first ejector panel (1) when it retracts for the second stroke, so that the first ejector panel (1) no longer moves with the second ejector panel (2).
2. The ejecting and resetting structure capable of returning the needle twice according to claim 1, wherein, The bottom end of the reset needle (3) is fixedly connected to the second ejector plate (2). A shoulder is provided in the middle of the reset needle (3). The shoulder abuts against the top of the first ejector plate (1) along the ejection direction of the oil cylinder (5).
3. The ejecting and resetting structure capable of returning the needle twice according to claim 2, characterized in that, The top of the first ejector plate (1) is provided with a countersunk hole, the shoulder of the reset return needle (3) passes through the countersunk hole, and a pad (6) is provided between the end face of the shoulder and the countersunk hole.
4. The ejecting and resetting structure capable of ejecting the needle twice according to claim 3, wherein, The bottom of the second ejector plate (2) is provided with an inverted stepped hole, and the top of the second ejector plate (2) is provided with a countersunk hole coaxially connected with the inverted stepped hole. A connecting screw extending into the hole is inserted in the inverted stepped hole, and the bottom end of the reset pin (3) extends into the countersunk hole and is fixedly connected with the connecting screw.
5. The ejecting and resetting structure capable of returning the needle twice according to any one of claims 1-4, characterized in that, The ejection linkage component (4) includes a connecting post (41), a limiting T-post (42), and a linkage slider (43). The linkage slider (43) is slidably disposed on the top of the second ejector panel (2). The limiting T-post (42) passes through the first ejector panel (1) from top to bottom, and the bottom end of the limiting T-post (42) is connected to one side of the linkage slider (43) by a sloping sliding fit. The connecting post (41) is disposed at the bottom of the first ejector panel (1). The bottom end of the connecting post (41) near the linkage slider (43) is provided with a slot that engages with the linkage slider (43). The side of the linkage slider (43) away from the connecting post (41) is provided with an elastic element.
6. The ejecting and resetting structure capable of ejecting a needle twice according to claim 5, wherein, The elastic element includes a spring (44), a guide post (45), and a baffle (46). The baffle (46) is located on the side of the linkage slider (43) away from the connecting post (41). The baffle (46) is provided with a guide post (45) on the side of the linkage slider (43). One end of the guide post (45) is engaged with the linkage slider (43) and simultaneously connected to the bottom of the limiting T post (42) through a sloping sliding fit. The outside of the guide post (45) is provided with a spring (44) between the baffle (46) and the linkage slider (43).
7. The ejecting and resetting structure capable of ejecting a needle twice according to claim 6, wherein, The bottom end of the limiting T-post (42) is provided with a pressing slope on the side near the guide post (45), and the pressing slope abuts against one end of the guide post (45).