A multi-stage delayed ejection mechanism for injection molds

Abstract

This invention provides a multi-stage delayed ejection mechanism for injection molds, belonging to the technical field of injection molded products. The ejection mechanism includes an upper mold, a lower mold, and a delayed ejection assembly. The upper mold and lower mold are joined along a first direction to form a cavity and an injection channel. The delayed ejection assembly includes a first ejector rod, a second ejector rod, and a blanking plate inserted into the lower mold along the first direction. The first ejector rod can extend into the cavity, the second ejector rod can extend into the injection channel, and the blanking plate is provided with a connecting hole. The first ejector rod, the second ejector rod, and the blanking plate can move sequentially towards the other side of the lower mold under external force. Under the push of the second ejector rod, part of the waste material is deformed under the constraint of the inner wall of the injection channel to move out of the lower mold along the first direction, and can be reset outside the lower mold. During the reset process, it collides with the blanking plate and moves away from the blanking plate to the waste recycling point under the collision action, realizing automatic waste recycling and improving waste recycling efficiency.

Description

Technical Field

[0001] This invention belongs to the field of injection molding technology, specifically relating to a multi-stage delayed ejection mechanism for injection molds. Background Technology

[0002] Injection molds consist of a molding system and a gating system. The melt is injected into the molding system through the gating system, where it forms the final product. In the gating system, it forms the sprue, also known as sprue or waste. The waste is not part of the final product and needs to be separated from the product and recycled after molding, either manually or automatically.

[0003] In existing technology, a multi-stage delayed ejection mechanism is used to eject the product. The ejector pin corresponding to the product ejects first, and the mold's constraint forces the connection between the scrap and the product to be severed. This separation of the product and scrap is achieved during the ejection process, after which the scrap is ejected and processed.

[0004] However, in different injection molding processes, the position of the waste material on the mold surface is not fixed after it is ejected from the mold. Therefore, the waste material is usually picked up manually and placed in a designated position, which results in low waste material handling efficiency. Summary of the Invention

[0005] The purpose of this application is to provide a multi-stage delayed ejection mechanism for injection molds, which solves the above-mentioned technical problems existing in the prior art.

[0006] This application is implemented as follows:

[0007] This application provides a multi-segment delayed ejection mechanism for injection molds, including an upper mold, a lower mold, and a delayed ejection assembly. The upper mold and lower mold are joined along a first direction to form a cavity and an injection channel. The injection channel includes a first segment located in the lower mold, the axis of which is inclined relative to the first direction and communicates with the cavity. The delayed ejection assembly includes a first ejector rod, a second ejector rod, and a blanking plate inserted into the lower mold along the first direction from the side of the lower mold away from the upper mold. The first ejector rod can extend into the cavity, the second ejector rod can extend into the injection channel, and the opening end of the first segment in the lower mold is located on the extension path of the second ejector rod. The blanking plate is provided with a connecting hole for communication. The hole can communicate with the first sub-segment, so that the inner wall of the communicating hole is flush with the inner wall of the first sub-segment; the first ejector, the second ejector, and the blanking plate can move sequentially toward the other side of the lower mold under the drive of external force, so that the product in the cavity and the waste in the injection channel are separated from the lower mold in sequence, and the blanking plate moves to the outside of the lower mold and blocks the product and waste; under the push of the second ejector, the waste corresponding to the first sub-segment is deformed under the restriction of the inner wall of the first sub-segment to move to the outside of the lower mold in the first direction, and can be reset outside the lower mold, and collide with the blanking plate during the reset process, thereby moving away from the blanking plate to the waste recycling point under the collision action.

[0008] The technical solution adopted in this invention can achieve the following beneficial effects:

[0009] In this application, during the ejection of the waste material from the lower mold, the waste material is constrained by the shape of the first segment, causing it to deform and store energy. After the waste material leaves the lower mold, the deformed portion rebounds and collides with the blanking plate. Under the impact of the collision with the blanking plate, the waste material bounces back and moves away from the blanking plate to the waste recycling point, thereby achieving automatic waste recycling and improving waste recycling efficiency. Furthermore, the blanking plate is provided with a connecting hole that connects to the injection channel, preventing the presence of the blanking plate from affecting the normal injection molding of the product. At the same time, the blanking plate moves after the second ejector pin moves, so that after the second ejector pin pushes the waste material out of the connecting hole, the blanking plate can be driven to move, thus preventing the waste material from affecting the movement of the blanking plate. Attached Figure Description

[0010] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram illustrating the interaction between waste materials and products;

[0012] Figure 2 This is a schematic diagram of the overall structure of the ejection mechanism provided in some embodiments of this application;

[0013] Figure 3 This is a schematic diagram illustrating the interaction between the ejection mechanism and waste and product according to some embodiments of this application;

[0014] Figure 4 This is a cross-sectional view of some of the ejection mechanisms provided in some embodiments of this application. Figure 1 ;

[0015] Figure 5 This application is about Figure 4 Detailed view of point A;

[0016] Figure 6 This is a schematic diagram showing the cooperation between the lower mold, the blanking plate, and the base plate provided in some embodiments of this application;

[0017] Figure 7 This is a schematic diagram of the structure of the feed plate provided in some embodiments of this application;

[0018] Figure 8 This is a schematic diagram of the cooperation between the second push rod and the transmission assembly provided in some embodiments of this application;

[0019] Figure 9 This is a schematic diagram of the structure of a cam provided in some embodiments of this application;

[0020] Figure 10 This is a cross-sectional view of some of the ejection mechanisms provided in some embodiments of this application. Figure 2 ;

[0021] Figure 11 This is a cross-sectional view of some of the ejection mechanisms provided in some embodiments of this application. Figure 3 ;

[0022] Figure 12 This is a cross-sectional view of some of the ejection mechanisms provided in some embodiments of this application. Figure 4 ;

[0023] Figure 13 This application is about Figure 12 Detailed image of point B;

[0024] Figure 14 This is a schematic diagram illustrating the cooperation between the first push rod and the adjusting plate and adjusting rod provided in some embodiments of this application;

[0025] Figure 15 This is a cross-sectional view of some of the ejection mechanisms provided in some embodiments of this application. Figure 5 .

[0026] In the diagram: 110-Upper mold, 120-Lower mold, 121-Adjusting groove, 130-Cavity, 140-Injection channel, 141-First sub-segment, 142-Open end, 200-Buffer assembly, 210-Buffer rod, 220-Buffer spring, 310-First ejector rod, 320-Second ejector rod, 321-First sub-rod, 322-Second sub-rod, 330-Short plate, 331-Connecting hole, 340-First protrusion, 350-Second protrusion, 400-Base, 500-Base plate, 510-First movable cavity 520-Second movable cavity, 530-Third movable cavity, 540-Movement channel, 550-Fourth movable cavity, 560-Assembly slot, 600-Support component, 700-Transmission assembly, 710-Roller, 720-Cam, 721-Protrusion, 722-Sizing part, 730-Gear, 740-Rack, 750-Third protrusion, 810-Adjusting plate, 820-First spring, 830-Adjusting rod, 831-Rod body, 832-Sleeve, 833-Second spring, 10-Scrap material, 20-Product. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0028] In the existing technology, after the waste material is ejected from the mold, its position on the mold surface is uncertain. The position of the waste material is different in different injection molding processes. It is difficult to automatically pick up the waste material. Therefore, the waste material is generally picked up manually.

[0029] The inventors discovered that during the ejection process from the mold, the waste material is confined by the inner wall of the gating system. During ejection, the waste material is compressed and deformed while simultaneously storing energy. After ejection, the waste material rebounds and collides with the product. Figure 1 As shown, Figure 1 In the diagram, the thicker dashed line represents the scrap after springback, the thinner dashed line represents the initial position of the scrap during forming, and the solid line represents the scrap after deformation. Under the interaction force between the two, the position of the scrap changes. Furthermore, after the product moves outside the mold, its position is not fixed, and the interaction force between the product and the scrap is unstable, resulting in an uncertain final position after the scrap collides with the product.

[0030] In view of this, embodiments of this application provide a multi-stage delayed ejection mechanism for injection molds, referencing... Figure 2 and Figure 3 As shown, it includes an upper mold 110, a lower mold 120, and a delayed ejection assembly.

[0031] The upper mold 110 and lower mold 120 are the main structures of the injection mold. The upper mold 110 and lower mold 120 are joined along a first direction to form a cavity 130 and an injection channel 140. The cavity 130 is part of the molding system, and the injection channel 140 is part of the gating system. The melt is injected into the cavity 130 through the injection channel 140. Ultimately, the product 20 is formed in the cavity 130, while the melt in the injection channel 140 forms waste 10. The injection channel 140 includes a first segment 141 located in the lower mold 120. The axis of the first segment 141 is inclined relative to the first direction and communicates with the cavity 130. The first segment 141 is a portion of the injection channel 140.

[0032] The delayed ejection assembly includes a first ejector pin 310, a second ejector pin 320, and a blanking plate 330 inserted into the lower mold 120 along a first direction from the side of the lower mold 120 away from the upper mold 110. The first ejector pin 310 extends into the cavity 130 to eject the product 20 from the cavity 130 out of the lower mold 120. The second ejector pin 320 extends into the injection channel 140, and a first segment 141 is located at the opening end 142 of the lower mold 120 along the extension path of the second ejector pin 320 to smoothly eject the scrap 10 from the injection channel 140 out of the lower mold 120. (Reference) Figure 7 As shown, the feed plate 330 is provided with a connecting hole 331, which can communicate with the first sub-segment 141, so that the inner wall of the connecting hole 331 is flush with the inner wall of the first sub-segment 141. (Refer to...) Figure 6 As shown, this is to prevent the material feed plate 330 from affecting the normal injection molding process.

[0033] The first ejector pin 310, the second ejector pin 320, and the blanking plate 330 can move sequentially toward the other side of the lower mold 120 under the drive of external force, so that the product 20 in the cavity 130 and the waste material 10 in the injection channel 140 are sequentially separated from the lower mold 120, and the blanking plate 330 moves to the lower mold 120 and blocks between the product 20 and the waste material 10.

[0034] The positions of the first ejector pin 310, the second ejector pin 320, and the blanking plate 330 relative to the lower mold 120 are adjustable. Before injection molding begins, the positions of the three components need to be adjusted, especially the positions of the first ejector pin 310 and the blanking plate 330, so that the first ejector pin 310 is positioned exactly at the edge of the product 20, and the inner wall of the connecting hole 331 of the blanking plate 330 is flush with the inner wall of the first sub-segment 141. The movement direction of the three components is along their insertion direction, i.e., the first direction.

[0035] The other side of the lower mold 120 refers to the side of the lower mold 120 closest to the upper mold 110. The first ejector pin 310, the second ejector pin 320, and the blanking plate 330 are pushed in sequence. The first ejector pin 310 first drives the product 20 in the cavity 130 to move out of the lower mold 120. At this time, the second ejector pin 320 is not activated, the position of the scrap 10 remains unchanged, and the connection between the scrap 10 and the product 20 is forcibly cut off. Then the second ejector pin 320 starts to move, pushing the scrap 10 to move out of the lower mold 120. After the scrap 10 exits the connecting hole, it begins to push the blanking plate 330 to move, and the blanking plate 330 can move smoothly out of the lower mold 120.

[0036] Under the push of the second push rod 320, the waste material 10 corresponding to the first segment 141 is deformed under the restriction of the inner wall of the first segment 141 to move to the outside of the lower mold 120 in the first direction, and can be reset outside the lower mold 120. During the reset process, it collides with the unloading plate 330 and moves to the waste recycling point in a direction away from the unloading plate 330 under the collision action.

[0037] Since the axis of the first segment 141 is inclined relative to the first direction, when the second push rod 320 pushes the scrap 10 along the first direction, the scrap 10 in the first segment 141 cannot maintain its structure as a whole and directly detach from the lower mold 120 along the first direction. This part of the scrap 10 can only detach from the lower mold 120 from the opening end 142 of the first segment 141 in the lower mold 120. Therefore, this part of the scrap 10 needs to be deformed in order to move out of the lower mold 120 along the first direction. After the waste material 10 moves outside the lower mold 120, the inner wall of the first segment 141 no longer restricts the waste material 10, and the waste material 10 begins to spring back and reset. During the reset process, the waste material 10 will collide with the unloading plate 330 located between the waste material 10 and the product 20. Under the impact, the waste material 10 is bounced away. If a waste recycling point is set at the final stopping position of the waste material 10, the waste material 10 can be automatically moved to the waste recycling point during the process of ejecting the waste material 10 from the lower mold 120, thereby achieving automatic recycling of the waste material 10 and improving the recycling efficiency of the waste material 10.

[0038] Furthermore, the feed plate 330 is located between the waste material 10 and the product 20, which can prevent the feed plate 330 from colliding with the product 20 during springback and affecting the surface structure of the product 20.

[0039] The positions of the blanking plate 330 and the lower mold 120 are stable, the collision between the blanking plate 330 and the scrap 10 is stable, the force and direction of the blanking plate 330 are also stable, and the scrap 10 can bounce back to the same area after colliding with the blanking plate 330.

[0040] It is important to note that, due to the connecting hole 331 on the blanking plate 330, attention must be paid to the distance by which the blanking plate 330 extends beyond the lower mold 120 and the area where the blanking plate 330 collides with the scrap 10, so that the scrap 10 can avoid the connecting hole 331 and collide with the blanking plate 330. Additionally, before injection molding, the position of the second ejector pin 320 in the injection channel 140 needs to be adjusted so that when the second ejector pin 320 pushes the scrap 10 outward from the lower mold 120, the end of the second ejector pin 320 and the scrap 10 in the first segment 141 can simultaneously detach from the lower mold 120.

[0041] For example, refer to Figure 4As shown, the second ejector pin 320 is located below the opening end 142 of the lower mold 120 in the first sub-segment 141. Scrap material 10 is also formed between the second ejector pin 320 and the opening end 142. The second ejector pin 320 pushes this scrap material 10 to move, thereby ejecting the scrap material 10 out of the lower mold 120 as a whole. The scrap material 10 between the second ejector pin 320 and the opening end 142, along with the scrap material 10 in the first sub-segment 141, simultaneously detaches from the lower mold 120, thus ensuring that the scrap material 10 can move stably until it detaches from the lower mold 120 under the push of the second ejector pin 320.

[0042] In some preferred embodiments of this application, when the connecting hole 331 is connected to the first sub-segment 141 and the inner wall of the connecting hole 331 is flush with the inner wall of the first sub-segment 141, the end of the blanking plate 330 is flush with the surface of the lower mold 120 near the upper mold 110. This ensures that even if the blanking plate 330 rises last, it can extend a sufficient distance beyond the lower mold 120, ensuring that the waste material 10 can collide with the blanking plate 330.

[0043] In some embodiments, the first push rod 310, the second push rod 320, and the unloading plate 330 can be connected to a drive mechanism, and the drive mechanism is activated in sequence to realize the sequential movement of the first push rod 310, the second push rod 320, and the unloading plate 330.

[0044] In other embodiments, the three components can be arranged together in the same component, and the connection between the component and the three components can be restricted, so that when the component is pushed, the three components are pushed outward in sequence.

[0045] For example, refer to Figure 2 and Figure 3 As shown, the ejection mechanism also includes a base 400 and a base plate 500. The lower mold 120 is fixed to the base 400 by a support member 600. The base plate 500 is installed between the base 400 and the lower mold 120, and the height of the support member 600 is greater than the thickness of the base plate 500. The gap between the base 400 and the lower mold 120 is greater than that between the base plate 500 and the lower mold 120, allowing the base plate 500 to move and change position between the base 400 and the lower mold 120.

[0046] refer to Figure 4As shown, the first ejector rod 310, the second ejector rod 320, and the blanking plate 330 are all inserted into the base plate 500. The first ejector rod 310 is fixed to the base plate 500. The second ejector rod 320 and the blanking plate 330 both penetrate the base plate 500 and contact the base 400. The second ejector rod 320 and the blanking plate 330 are movable with the base plate 500. During the process of the base plate 500 moving towards the lower mold 120 under the action of external force, the moving distance of the base plate 500 relative to the second ejector rod 320 is less than the moving distance of the base plate 500 relative to the blanking plate 330. The base plate 500 sequentially pushes the first ejector rod 310, the second ejector rod 320, and the blanking plate 330 to move.

[0047] The first ejector pin 310 is fixed to the base plate 500. When the base plate 500 is pushed, the first ejector pin 310 is moved synchronously, ejecting the product 20 from the cavity 130 out of the lower mold 120. The base plate 500 can move relative to the second ejector pin 320 and the blanking plate 330, and the relative movement distance between the base plate 500 and the two is limited. When the movement distance between the base plate 500 and the two reaches its limit, the two can be driven to move. Moreover, the movement distance of the base plate 500 relative to the second ejector pin 320 is less than the movement distance of the base plate 500 relative to the blanking plate 330. Thus, during the movement, the base plate 500 achieves the effect of driving the second ejector pin 320 first, and then driving the blanking plate 330.

[0048] In some embodiments, a top shaft is provided below the base plate 500. The top shaft rises to drive the base plate 500 to move, and the base 400 is provided with a through hole for the top shaft to pass through.

[0049] In some specific embodiments of this application, reference is made to Figure 5 As shown, a first protrusion 340 can be provided on the peripheral sidewall of the feed plate 330, and a first movable cavity 510 is provided in the bottom plate 500. The first protrusion 340 is movably disposed in the first movable cavity 510 along a first direction. The first protrusion 340 can move in the first movable cavity 510. When the bottom plate 500 moves relative to the feed plate 330, the first movable cavity 510 moves relative to the first protrusion 340 until the end of the first movable cavity 510 abuts against the first protrusion 340. The first movable cavity 510 can no longer move relative to the first protrusion 340. The bottom plate 500 can continue to move to drive the feed plate 330 to move synchronously.

[0050] A second protrusion 350 is provided on the peripheral side wall of the second push rod 320, and a second movable cavity 520 is provided in the base plate 500. The second protrusion 350 is movably disposed in the second movable cavity 520 along the first direction. The second protrusion 350 can move in the second movable cavity 520. When the base plate 500 moves relative to the second push rod 320, the second movable cavity 520 moves relative to the second protrusion 350 until the end of the second movable cavity 520 abuts against the second protrusion 350. The second movable cavity 520 can no longer move relative to the second protrusion 350. The base plate 500 can continue to move to drive the second push rod 320 to move synchronously.

[0051] When the base plate 500 moves toward the lower mold 120, the moving distance of the first movable cavity 510 relative to the first protrusion 340 is greater than the moving distance of the second movable cavity 520 relative to the second protrusion 350, thereby achieving the effect that the base plate 500 first pushes the second push rod 320 to move, and then pushes the unloading plate 330 to move.

[0052] In some preferred embodiments of this application, the ejection mechanism further includes a transmission assembly 700, and the second ejector rod 320 includes a first sub-rod 321 and a second sub-rod 322. (See reference...) Figure 8 As shown, one end of the first sub-rod 321 is inserted into the base plate 500, and the other end is located between the base plate 500 and the lower mold 120. One end of the second sub-rod 322 is inserted into the lower mold 120, and the other end is located between the lower mold 120 and the base plate 500. The transmission assembly 700 is connected between the base plate 500 and the junction of the first ejector rod 310 and the second ejector rod 320. The transmission assembly 700 is connected between the base plate 500 and the second ejector rod 320, and the connection position with the second ejector rod 320 is the junction position of the first sub-rod 321 and the second sub-rod 322 of the second ejector rod 320.

[0053] After the base plate 500 moves toward the lower mold 120 and pushes the first ejector pin 310, the transmission assembly 700 can drive the second sub-pin 322 to move away from the lower mold 120 under the push of the base plate 500, thereby separating the second sub-pin 322 from the scrap 10 in the injection channel 140. As the second sub-pin 322 moves away from the lower mold 120, the scrap 10 cannot move downwards in the injection channel 140, thus separating the second sub-pin 322 from the scrap 10. When the scrap 10 is ejected from the lower mold 120 and pops out after colliding with the blanking plate 330, the resistance caused by the second ejector pin 320 to the scrap 10 is almost negligible, the predictable movement distance of the scrap 10 is more accurate, and the probability of the scrap 10 moving to the scrap recycling area is greater.

[0054] In some embodiments of this application, reference may be made to Figure 8As shown, the transmission assembly 700 includes a rotating wheel 710, a cam 720, a gear 730, and a rack 740. The end of the first sub-rod 321 is connected to one of the rotating wheel 710 and the cam 720, and the end of the second sub-rod 322 is connected to the other of the rotating wheel 710 and the cam 720. Here, the ends of the first sub-rod 321 and the second sub-rod 322 refer to the ends located between the base plate 500 and the lower mold 120. The peripheral wall of the cam 720 abuts against the peripheral wall of the rotating wheel 710, and the two drive each other; rotation of one can drive rotation of the other. The gear 730 is coaxially fixed to either the cam 720 or the rotating wheel 710 at the end of the first sub-rod 321; rotation of one can drive rotation of the other. The rack 740 is installed between the base plate 500 and the lower mold 120, and the gear 730 and rack 740 are meshed together, driving each other. The cam 720 includes a protrusion 721 and a sizing portion 722 arranged circumferentially thereon. Along the circumference of the cam 720, the radius of the sizing portion 722 remains constant, while the radius of the protrusion 721 gradually decreases until it is the same as the radius of the sizing portion 722. (See reference...) Figure 9 As shown.

[0055] When the base plate 500 is in contact with the base 400, the protrusion 721 of the cam 720 abuts against the rotating wheel 710. After the base plate 500 moves toward the lower mold 120 and pushes the first push rod 310, the base plate 500 can drive the gear 730 to rotate through the meshing of the rack 740 and the gear 730. The cam 720 or the rotating wheel 710 rotates synchronously with the gear 730, so that the part of the cam 720 that abuts against the rotating wheel 710 changes from the protrusion 721 to the sizing part 722, so that the second sub-rod 322 moves toward the base plate 500.

[0056] As the base plate 500 moves toward the lower mold 120, it will push one of the rack 740 and the gear 730 to move, causing the gear 730 to rotate relative to the rack 740. The cam 720 or the rotating wheel 710 connected synchronously with the gear 730 will also rotate. The position where the cam 720 abuts against the rotating wheel 710 can be switched from the protrusion 721 to the sizing part 722. The sizing part 722 has a smaller radius. The second sub-rod 322 moves toward the base plate 500, realizing the separation of the second sub-rod 322 from the waste material 10.

[0057] In some implementation methods, reference may be made to Figure 10 As shown, the base plate 500 is provided with a movable channel 540 that runs through both ends of its axial direction. One end of the rack 740 is fixed to the lower mold 120, and the other end of the rack 740 is provided in the movable channel 540. During the process of the base plate 500 pushing the second push rod 320 to move towards the lower mold 120, the drive gear 730 rotates along the rack 740.

[0058] The upward movement of the base plate 500 can push the gear 730 upward. Since the gear 730 is meshed with the rack 740, as the gear 730 moves upward, the gear 730 rotates along the rack 740, thereby driving the rotating wheel 710 or cam 720, which is fixed coaxially with the gear 730, to rotate. The part that drives the cam 720 and the rotating wheel 710 to abut is changed from the protrusion 721 to the sizing part 722.

[0059] In other embodiments, reference is made to Figure 11 As shown, one end of the rack 740 is movably inserted into the lower mold 120, and the other end is movably disposed on the base plate 500 and in contact with the base 400. A third protrusion 750 is provided on the peripheral side wall of the rack 740. A third movable cavity 530 is provided in the base plate 500. The third protrusion 750 is movably disposed in the third movable cavity 530. During the process of the base plate 500 moving towards the lower mold 120 under the action of external force, the moving distance of the base plate 500 relative to the second push rod 320 is greater than the moving distance of the third protrusion 750 in the third movable cavity 530. The base plate 500 pushes the rack 740 and the second push rod 320 to move in sequence. The gear 730 rotates as the base plate 500 pushes the rack 740 to move.

[0060] During the ascent of the base plate 500, the third protrusion 750 first abuts against the end of the third movable cavity 530, and then the rack 740 rises synchronously with the base plate 500. The rack 740 moves upward, thereby driving the gear 730 meshing with it to rotate, which in turn drives the gear 730 or the rotating wheel 710 fixed coaxially with the gear 730 to rotate. After the base plate 500 reaches the endpoint of its movement relative to the second push rod 320, the base plate 500 then pushes the second push rod 320 to move.

[0061] The first ejector pin 310 is used to eject the product 20 from the lower mold 120. Generally, there are at least two first ejector pins 310, which facilitates ejecting the product 20 from the lower mold 120. In some embodiments, refer to... Figure 12 and Figure 13 As shown, a fourth movable cavity 550 is provided inside the base plate 500. An adjustment groove 121 is provided on the surface of the lower mold 120 near the base plate 500. An adjustment plate 810 and a first spring 820 are movably installed inside the fourth movable cavity 550. The first spring 820 is located on the side of the adjustment plate 810 away from the lower mold 120. An adjustment rod 830 is fixed to the adjustment plate 810. The other end of the adjustment rod 830 is inserted into the adjustment groove 121. One of the first push rods 310 is fixedly connected to the adjustment plate 810.

[0062] As the base plate 500 pushes the first ejector rod 310 toward the lower mold 120, the adjusting rod 830 moves within the adjusting groove 121 until it abuts against the bottom of the adjusting groove 121. The adjusting rod 830 can no longer move upward. As the base plate 500 continues to move upward, the adjusting rod 830 begins to compress the first spring 820, thereby driving the adjusting plate 810 and the first ejector rod 310 fixed to the adjusting plate 810 to move away from the product 20 in the cavity 130, so that the first ejector rod 310 separates from the product 20.

[0063] After the adjusting rod 830 abuts against the bottom of the adjusting groove 121, the adjusting rod 830 can no longer move upward. The other end of the adjusting rod 830 is connected to the adjusting plate 810. The adjusting plate 810 and the first push rod 310 fixed to the adjusting plate 810 can no longer move upward. However, since the first spring 820 is provided below the adjusting plate 810, the first spring 820 can be compressed to allow the base plate 500 to continue to rise. The other push rods fixed to the base plate 500 also continue to rise, lifting the product 20. With the product 20 as a reference, the adjusting plate 810 and the first push rod 310 fixed to the adjusting plate 810 move in a direction away from the product 20.

[0064] It should be noted that after the first spring 820 is compressed to its limit position, the base plate 500 will not be able to rise further. Therefore, it is necessary to pay attention to the compressibility of the first spring 820 to ensure that the product 20 has been ejected from the lower mold 120 when the first spring 820 is compressed to its limit position.

[0065] Since one of the first ejector pins 310 separates from the product 20, after the product 20 is removed from the lower mold 120, the remaining first ejector pin 310 has poor support stability for the product 20. Under its own gravity, the product 20 is prone to tilting and falling directly, thus achieving the separation of the product 20 from the remaining first ejector pin 310.

[0066] In some preferred embodiments, reference Figure 13 and Figure 14 As shown, the adjusting rod 830 includes a rod body 831, a sleeve 832, and a second spring 833. One end of the rod body 831 is fixedly connected to the adjusting plate 810. The sleeve 832 is sleeved on the other end of the rod body 831 and inserted into the adjusting groove 121. The second spring 833 is sleeved on the outside of the rod body 831 and is pressed against the end of the adjusting plate 810 and the end of the sleeve 832. There is a gap between the end of the sleeve 832 and the end of the rod body 831. After the sleeve 832 abuts against the bottom of the adjusting groove 121, as the base plate 500 continues to move upward, the sleeve 832 can compress the second spring 833, providing a buffering effect.

[0067] In some embodiments of this application, at least one set of buffer components 200 is further provided between the lower mold 120 and the base plate 500, as can be referred to Figure 15 As shown, the buffer assembly 200 includes a buffer rod 210 and a buffer spring 220. The buffer rod 210 is fixedly installed on the base 400 or the base plate 500 and movably inserted into the lower mold 120. The buffer spring 220 is sleeved on the buffer rod 210 and is pressed against the lower mold 120 and the base plate 500. The buffer assembly 200 provides a buffering effect, preventing the base plate 500 from directly colliding with the lower mold 120.

[0068] In some embodiments, the base plate 500 is provided with an assembly groove 560, and the support member 600 passes through the assembly groove 560, with the peripheral sidewall of the support member 600 contacting and engaging with the inner wall of the assembly groove 560. The support member 600, fixed between the base 400 and the lower mold 120, can guide the movement of the base plate 500, so that the base plate 500 moves closer to or away from the lower mold 120 in a preset first direction.

[0069] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0070] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0071] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-stage delayed ejection mechanism for an injection mold, characterized by, The injection molding machine comprises an upper mold, a lower mold and a delayed ejection assembly, the upper mold and the lower mold are butted along a first direction to form a cavity and an injection channel, the injection channel comprises a first sub-section of the lower mold, an axis of the first sub-section is inclined relative to the first direction and communicates with the cavity; The delayed ejection assembly comprises a first ejector pin, a second ejector pin and a stripper plate which are inserted into the lower mold from a side of the lower mold away from the upper mold along the first direction, the first ejector pin is capable of extending into the cavity, the second ejector pin is capable of extending into the injection channel, and the first sub-section is located on an extension path of the second ejector pin at an open end of the lower mold, the stripper plate is provided with a communication hole which is capable of communicating with the first sub-section so that an inner wall of the communication hole is flush with an inner wall of the first sub-section; The first ejector pin, the second ejector pin and the stripper plate are capable of moving toward the other side of the lower mold in sequence under the drive of an external force so that a product in the cavity and waste in the injection channel are sequentially separated from the lower mold, the stripper plate moves out of the lower mold and blocks between the product and the waste; Under the push of the second ejector pin, part of the waste corresponding to the first sub-section is deformed under the limitation of the inner wall of the first sub-section to move out of the lower mold along the first direction, and can be reset outside the lower mold and collide at the stripper plate during the resetting process so as to move to a waste recovery place in a direction away from the stripper plate under the collision effect; The ejection mechanism further comprises a base and a bottom plate, the lower mold is fixed to the base through a support, the bottom plate is installed between the base and the lower mold, and the height of the support is greater than the thickness of the bottom plate; The first ejector pin, the second ejector pin and the stripper plate are all inserted into the bottom plate, the first ejector pin is fixed to the bottom plate, the second ejector pin and the stripper plate both penetrate through the bottom plate and contact with the base, the second ejector pin and the stripper plate are both movably matched with the bottom plate, during the movement of the bottom plate toward the lower mold under the action of an external force, the moving distance of the bottom plate relative to the second ejector pin is less than the moving distance of the bottom plate relative to the stripper plate, and the bottom plate sequentially pushes the first ejector pin, the second ejector pin and the stripper plate to move.

2. The multi-stage delayed ejection mechanism for injection mold according to claim 1, wherein A first protrusion is arranged on a peripheral side wall of the stripper plate, a first movable cavity is arranged in the bottom plate, the first protrusion is movably arranged in the first movable cavity along the first direction, a second protrusion is arranged on a peripheral side wall of the second ejector pin, a second movable cavity is arranged in the bottom plate, and the second protrusion is movably arranged in the second movable cavity along the first direction.

3. The multi-stage delayed ejection mechanism for injection mold according to claim 1, wherein, The ejection mechanism further comprises a transmission assembly, the second ejector pin comprises a first sub-rod and a second sub-rod, one end of the first sub-rod is inserted into the bottom plate, and the other end is located between the bottom plate and the lower mold, one end of the second sub-rod is inserted into the lower mold, and the other end is located between the lower mold and the bottom plate, and the transmission assembly is connected between the bottom plate and the joint position of the first ejector pin and the second ejector pin. After the bottom plate moves towards the lower mold and pushes the first top rod, the transmission assembly can drive the second sub-rod to move away from the lower mold under the pushing of the bottom plate, so that the second sub-rod is separated from the waste in the injection channel.

4. The multi-stage delayed ejection mechanism for injection mold according to claim 3, wherein The transmission assembly comprises a rotating wheel, a cam, a gear and a rack; The end of the first sub-rod is connected to one of the rotating wheel and the cam, the end of the second sub-rod is connected to the other one of the rotating wheel and the cam, the circumferential wall of the cam is in abutting fit with the circumferential wall of the rotating wheel, the gear is coaxially fixed with the cam or the rotating wheel installed at the end of the first sub-rod, the rack is installed between the bottom plate and the lower mold, and the gear is in meshing arrangement with the rack; The cam comprises a convex part and a constant-diameter part arranged along the circumference of the cam, along the circumference of the cam, the radius of the constant-diameter part remains unchanged, and the radius of the convex part gradually decreases to be the same as the radius of the constant-diameter part; When the bottom plate is in contact with the base, the convex part of the cam is in abutting fit with the rotating wheel, after the bottom plate moves towards the lower mold and pushes the first top rod, the bottom plate can drive the gear to rotate through the meshing of the rack and the gear, the cam or the rotating wheel rotates synchronously with the gear, so that the part where the cam is in abutting fit with the rotating wheel is switched from the convex part to the constant-diameter part, so that the second sub-rod moves towards the bottom plate.

5. The multi-stage delayed ejection mechanism for injection mold according to claim 4, wherein The bottom plate is provided with a movable channel penetrating through the axial two end faces, one end of the rack is fixed to the lower mold, and the other end of the rack is movably arranged in the movable channel; during the movement of the second top rod towards the lower mold pushed by the bottom plate, the gear is driven to rotate along the rack; Or one end of the rack is movably inserted into the lower mold, and the other end is movably arranged in the bottom plate, the circumferential wall of the rack is provided with a third protrusion, a third movable cavity is arranged in the bottom plate, the third protrusion is movably arranged in the third movable cavity, during the movement of the bottom plate towards the lower mold under the action of external force, the movement distance of the bottom plate relative to the second top rod is greater than the movement distance of the third protrusion in the third movable cavity, the bottom plate sequentially pushes the rack and the second top rod to move, and the bottom plate drives the gear to rotate by pushing the rack.

6. The multi-stage delayed ejection mechanism for injection mold according to claim 1, wherein The first top rod is not less than two, the fourth movable cavity is arranged in the inside of the bottom plate, the surface of the lower mold close to the bottom plate is provided with an adjusting groove, an adjusting plate and a first spring are movably arranged in the fourth movable cavity, the first spring is located on the side of the adjusting plate away from the lower mold, the adjusting plate is fixed with an adjusting rod, the other end of the adjusting rod is inserted into the adjusting groove, and one of the first top rods is fixedly connected with the adjusting plate. During the process that the bottom plate pushes the first top rod to move towards the lower mold, the adjusting rod moves in the adjusting groove until abutting to the bottom of the adjusting groove, the adjusting rod compresses the first spring, so that the adjusting plate and the first top rod fixed with the adjusting plate move away from the product in the cavity, so that the first top rod is separated from the product.

7. The multi-stage delayed ejection mechanism for injection mold according to claim 6, wherein The adjusting rod comprises a rod body, a sleeve and a second spring, one end of the rod body is fixedly connected with the adjusting plate, the sleeve is sleeved outside the other end of the rod body and is inserted into the adjusting groove, the second spring is sleeved outside the rod body, and the second spring is tightly abutted between the adjusting plate and the end of the sleeve, and the end of the sleeve and the end of the rod body have a gap.

8. The multi-stage delayed ejection mechanism for injection mold according to claim 1, wherein, At least one set of buffer assemblies is further arranged between the lower mold and the bottom plate, the buffer assembly comprises a buffer rod and a buffer spring, the buffer rod is fixedly installed on the bottom plate or the base and movably inserted into the lower mold, the buffer spring is sleeved outside the buffer rod, and the buffer spring is tightly abutted between the lower mold and the bottom plate. And / or, the bottom plate is provided with an assembly groove, the support is penetrated in the assembly groove, and the circumferential wall of the support is in contact with the inner wall of the assembly groove.

9. The multi-stage delayed ejection mechanism for injection mold according to claim 1, wherein, In the case that the communication hole communicates with the first sub-section, the inner wall of the communication hole is flush with the inner wall of the first sub-section, and the end of the blanking plate is flush with the surface of the lower mold close to the upper mold.

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