A new structure of ejecting screw post

Abstract

This utility model discloses a novel ejection structure for a screw post, including a base plate with symmetrically mounted mold feet. A lower mold base is fitted on the top of the two mold feet, and a lower mold core is provided on the top of the lower mold base. A top plate and a push plate are arranged sequentially above the base plate. A placement groove is provided at the bottom of the top plate, and a needle plate is placed in the placement groove. An inner needle and an ejector sleeve extending upward and penetrating to the lower mold core are respectively fixedly mounted on the needle plate and the push plate. The ejector sleeve is slidably sleeved on the inner needle, and its upper end face is located below the upper end face of the inner needle. The base plate has a plurality of KO holes, and each of the plurality of KO holes has a KO post. The plurality of KO posts are fixedly connected to the top plate. The needle plate has a limiting component. One side of one of the KO posts is recessed to form a stepped surface that corresponds to the upper and lower parts of the needle plate and is spaced apart. After the needle plate of this utility model is limited, the KO post can still push the top plate and the push plate to continue moving, avoiding interference between the needle plate and the KO post, which would prevent the ejector sleeve and the inner needle from being ejected in sections.

Description

Technical Field

[0001] This utility model relates to the field of injection mold technology, specifically a novel ejection structure for a screw post. Background Technology

[0002] Plastic molds are tools used to process and shape plastic products. They enable mass production by giving plastic specific shapes and precise dimensions. They are widely used in the automotive, home appliance, and electronics industries. Their core structure includes moving molds, fixed molds, and systems for gating, temperature control, and ejection.

[0003] In injection molding, when a product structure contains tall screws, conventional ejection mechanisms are difficult to effectively demold due to their height, which can easily cause product deformation. To solve this problem, ejector sleeves (also known as ejector pins) are usually used for ejection. The axial movement of the ejector sleeve pushes the screws out of the core.

[0004] However, in practical applications, a situation may occur where the ejector pin inside the sleeve hits the KO hole and interferes with it, causing the ejection action to be obstructed and affecting the product ejection. Utility Model Content

[0005] The purpose of this utility model is to provide a novel ejection structure for a screw post, so as to solve the problems mentioned in the background art.

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

[0007] A novel ejection structure for a screw post includes a base plate on which mold feet are symmetrically mounted. A lower mold base is fitted on the top of each of the two mold feet. A lower mold core is provided on the top of the lower mold base. A top plate and a push plate are sequentially arranged above the base plate. A placement groove is provided at the bottom of the top plate, in which a needle plate is placed. An inner needle extending upward and penetrating to the lower mold core and a sleeve are respectively fixedly mounted on the needle plate and the push plate. The sleeve is slidably fitted over the inner needle, and its upper end face is located below the upper end face of the inner needle. The base plate has a plurality of KO holes, each containing a KO post. The KO posts are fixedly connected to the top plate. The needle plate has a limiting component, and one side of one of the KO posts is recessed to form a stepped surface corresponding to the upper and lower parts of the needle plate with a gap.

[0008] Furthermore, the limiting assembly includes a limiting rod and a limiting sleeve. The limiting rod is fixedly connected to the base plate and passes through the needle plate, top plate, and push plate in sequence. Its top is fixedly inserted into the lower mold base. The limiting sleeve is movably sleeved on the outside of the limiting rod, with its bottom located in the placement groove and abutting against the top of the needle plate. The limiting sleeve passes through the top plate and push plate in sequence from bottom to top, with its upper end face located below the lower end face of the lower mold base and maintaining a certain distance from the lower mold base.

[0009] Furthermore, the distance between the stepped surface and the needle plate is slightly greater than the distance between the upper end face of the ejector sleeve and the upper end face of the inner needle.

[0010] Furthermore, a guide rod is fixedly installed on the base plate, and the guide rod passes through the needle plate, the top plate and the push plate in sequence, with its top fixedly inserted into the lower mold base.

[0011] Furthermore, a plurality of push rods are installed on the top of the top plate, and the plurality of push rods pass through the push plate and the lower mold base in sequence. A return spring is sleeved on the outside of the plurality of push rods, and one end of the plurality of return springs abuts against the top of the push plate and the other end abuts against the bottom of the lower mold base.

[0012] Furthermore, a number of guide posts are installed on the base plate, and the guide posts pass through the top plate and the push plate in sequence, with their upper end face abutting against the lower end face of the lower mold base.

[0013] The beneficial effects of this utility model are:

[0014] This invention utilizes the injection molding machine's push rod to drive the KO column upwards. The KO column causes the top plate and push plate to move upwards as a whole. The top plate and push plate then cause the ejector sleeve to rise, lifting the product and ejecting it from the lower mold core. Due to the adhesion between the inner pin and the product, the inner pin and the pin plate fixedly connected to it are also driven upwards. When the ejection motion reaches a certain distance, the pin plate is stopped by the limiting component. At this point, the top plate and push plate can continue to move upwards under the continuous push of the KO column, allowing the ejector sleeve to move further upwards relative to the stationary inner pin, thereby completing the secondary ejection action on the cylindrical part of the product. This achieves complete separation of the product from the inner pin, avoiding the problem of product deformation or damage that may occur during a single ejection.

[0015] In this invention, one side of one of the KO columns is recessed to form a stepped surface that corresponds to the upper and lower parts of the needle plate and is spaced apart. This structure is used to avoid the needle plate, so that after the needle plate is limited, the KO column can continue to push the top plate and push plate to move, avoiding interference between the needle plate and the KO column, which would prevent the ejector sleeve and inner needle from being ejected in sections.

[0016] Other features and advantages of this invention will be described in detail in the following detailed description section. Attached Figure Description

[0017] Figure 1 : Overall structural diagram of this utility model.

[0018] Figure 2 : Bottom structure diagram of this utility model.

[0019] Figure 3 Cross-sectional view of this utility model Figure 1 .

[0020] Figure 4 : A cross-sectional view of the top plate of this utility model.

[0021] Figure 5 Cross-sectional view of this utility model Figure 2 .

[0022] Figure 6 : Figure 4 Enlarged view of the structure of part A.

[0023] Figure 7 : Figure 4 Enlarged view of the structure of part B.

[0024] Reference numerals: 1. Base plate; 2. Mold foot; 3. Lower mold base; 4. Top plate; 5. Push plate; 6. Needle plate; 11. KO hole; 12. KO pillar; 13. Step surface; 14. Guide rod; 15. Guide pillar; 31. Lower mold core; 41. Placement slot; 42. Ejector rod; 43. Return spring; 61. Inner needle; 62. Sleeve; 63. Limiting assembly; 631. Limiting rod; 632. Limiting sleeve. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0026] Please refer to Figure 1-7 ;

[0027] A novel ejection structure for a screw post includes a base plate 1. Mold feet 2 are symmetrically mounted on the base plate 1. A lower mold base 3 is fitted onto the top of each mold foot 2. A lower mold core 31 is located on the top of the lower mold base 3. The lower mold core 31 cooperates with an upper mold core (not shown in the figure). When the upper mold base and lower mold base 3 are closed, they together form a complete mold cavity, from which the desired product can be produced by injection molding. A top plate 4 and a push plate 5 are sequentially arranged above the base plate 1. A placement groove 41 is provided at the bottom of the top plate 4, and a pin plate 6 is placed in the placement groove 41. An inner pin 61 extending upwards and penetrating to the lower mold core 31 and an ejector sleeve 62 are respectively fixedly mounted on the pin plate 6 and the push plate 5. The ejector sleeve 62 is slidably sleeved on the inner pin 61, with its upper end face located below the upper end face of the inner pin 61, and is used to participate in forming the cylindrical structure of the product during the product molding process. The base plate 1 has several KO holes 11, each containing a KO pillar 12, which is fixedly connected to the top plate 4. When the mold completes injection and enters the mold opening stage, the injection molding machine push rod acts on the bottom of the KO pillar 12, pushing it upward, thereby causing the top plate 4 and push plate 5 to rise as a whole, achieving the ejection action. Because the plastic material adheres to the surface of the inner pin 61 during cooling and solidification, the inner pin 61 will move along with the product during ejection. To achieve complete demolding of the product, the pin plate 6 is equipped with a limiting component 63 to limit its upward stroke, thus achieving segmented ejection, ejecting the product in segments, and separating the product from the inner pin 61. One side of one of the KO pillars 12 is recessed to form a stepped surface 13 that corresponds vertically to and is spaced apart from the needle plate 6. This structure is used to avoid the needle plate 6, so that after the needle plate 6 is limited, the KO pillar 12 can still continue to push the top plate 4 and the push plate 5 to move, avoiding interference between the needle plate 6 and the KO pillar 12, which would prevent the ejector sleeve 62 and the inner needle 61 from being ejected in stages. It should be noted that the distance between the stepped surface 13 and the needle plate 6 is slightly greater than the distance between the upper end face of the ejector sleeve 62 and the upper end face of the inner needle 61. That is, the secondary ejection distance of the ejector sleeve 62 is greater than the depth of the cylindrical structure of the product, to ensure that the cylindrical part of the product is completely separated from the inner needle 61, achieving complete demolding.

[0028] The specific working process is as follows: After the product injection molding is completed, the mold enters the mold opening stage. The injection molding machine push rod pushes the KO column 12 to move upward. The KO column 12 drives the top plate 4 and push plate 5 to move upward as a whole. The top plate 4 and push plate 5 drive the ejector sleeve 62 to rise. The ejector sleeve 62 lifts the product and ejects the product from the lower mold core 31. Due to the adhesion between the inner pin 61 and the product, the inner pin 61 and the pin plate 6 fixedly connected to it are also driven upward. When the ejection movement reaches a certain distance, the pin plate 6 is blocked by the limiting component 63 and stops moving. At this time, the top plate 4 and push plate 5 can continue to move upward under the continuous push of the KO column 12, so that the ejector sleeve 62 moves further upward relative to the stationary inner pin 61, thereby completing the secondary ejection action of the cylindrical part of the product, realizing the complete separation of the product from the inner pin 61, and avoiding the problem of product deformation or damage that may occur due to one-time ejection.

[0029] In this embodiment, the limiting component 63 includes a limiting rod 631 and a limiting sleeve 632. The limiting rod 631 is fixedly connected to the base plate 1 and passes through the needle plate 6, the top plate 4, and the push plate 5 in sequence. Its top is fixedly inserted into the lower mold base 3 to ensure that it remains stationary throughout the ejection process. The limiting sleeve 632 is movably sleeved on the outside of the limiting rod 631 and is guided by the limiting rod 631. Its bottom is located in the placement groove 41 and abuts against the top of the needle plate 6. When the needle plate 6 moves upward, it can drive the limiting sleeve 632 to move upward synchronously. The limiting sleeve 632 passes through the top plate 4 and the push plate 5 in sequence from bottom to top. Its upper end face is located below the lower end face of the lower mold base 3 and maintains a certain distance from the lower mold base 3. As the ejection stroke progresses, the limiting sleeve 632 gradually approaches the lower mold base 3. When it rises to the limited stroke position, the upper end face of the limiting sleeve 632 contacts and abuts against the lower end face of the lower mold base 3. At this time, the rising of the limiting sleeve 632 is blocked by the lower mold base 3, thus stopping its movement and causing the needle plate 6 to stop moving as well. After the needle plate 6 and the limiting sleeve 632 stop moving, the ejector sleeve 62 continues to move upward with the push plate 5 and the top plate 4, thereby realizing the independent secondary ejection action of the ejector sleeve 62 relative to the inner needle 61, and finally completely separating the cylindrical structure on the product from the inner needle 61, completing the demolding.

[0030] In this embodiment, a guide rod 14 is fixedly installed on the base plate 1. The guide rod 14 passes through the needle plate 6, the top plate 4 and the push plate 5 in sequence, and its top is fixedly inserted into the lower mold base 3. The guide rod 14 guides the lifting and lowering movement of the needle plate 6.

[0031] In this embodiment, a plurality of ejector rods 42 are installed on the top of the top plate 4. The ejector rods 42 pass through the push plate 5 and the lower mold base 3 in sequence. A return spring 43 is sleeved on the outside of the ejector rods 42. One end of the return spring 43 abuts against the top of the push plate 5 and the other end abuts against the bottom of the lower mold base 3. When the top plate 4 is pushed upward by the KO column 12, the return spring 43 is compressed. When the ejection action is completed and the injection molding machine push rod retracts, the return spring 43 releases the compression force, pushing the push plate 5, the top plate 4 and each ejection component back to the initial position.

[0032] In this embodiment, a number of guide posts 15 are installed on the base plate 1. The guide posts 15 pass through the top plate 4 and the push plate 5 in sequence, and their upper end face abuts against the lower end face of the lower mold base 3. The guide posts 15 guide the lifting and lowering movement of the top plate 4 and the push plate 5.

[0033] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0034] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims

1. A novel ejection structure for a screw post, comprising a base plate (1), on which mold feet (2) are symmetrically mounted, and a lower mold base (3) is fitted on the top of the two mold feet (2), the top of the lower mold base (3) being provided with a lower mold core (31), and a top plate (4) and a push plate (5) are sequentially arranged above the base plate (1), characterized in that, The bottom of the top plate (4) is provided with a placement groove (41), in which a needle plate (6) is placed. The needle plate (6) and the push plate (5) are respectively fixedly installed with an inner needle (61) extending upward and penetrating to the lower mold core (31) and a sleeve (62). The sleeve (62) is slidably sleeved on the inner needle (61), and its upper end face is located below the upper end face of the inner needle (61). The bottom plate (1) is provided with a plurality of KO holes (11), and each of the plurality of KO holes (11) is provided with a KO post (12). The plurality of KO posts (12) are fixedly connected to the top plate (4). The needle plate (6) is provided with a limiting component (63). One side of one of the KO posts (12) is recessed to form a stepped surface (13) that corresponds to the needle plate (6) and is spaced apart.

2. A novel ejection structure of a screw post according to claim 1, characterized in that, The limiting component (63) includes a limiting rod (631) and a limiting sleeve (632). The limiting rod (631) is fixedly connected to the base plate (1) and passes through the needle plate (6), the top plate (4) and the push plate (5) in sequence. The top is fixedly inserted into the lower mold base (3). The limiting sleeve (632) is movably sleeved on the outside of the limiting rod (631). Its bottom is located in the placement groove (41) and abuts against the top of the needle plate (6). The limiting sleeve (632) passes through the top plate (4) and the push plate (5) in sequence from bottom to top. Its upper end face is located below the lower end face of the lower mold base (3) and maintains a certain distance from the lower mold base (3).

3. The new ejection structure of a screw post according to claim 1, characterized in that, The distance between the stepped surface (13) and the needle plate (6) is slightly greater than the distance between the upper end face of the sleeve (62) and the upper end face of the inner needle (61).

4. The new ejection structure of a screw post according to claim 1, characterized in that, A guide rod (14) is fixedly installed on the base plate (1). The guide rod (14) passes through the needle plate (6), the top plate (4) and the push plate (5) in sequence, and its top is fixedly inserted into the lower mold base (3).

5. The new ejection structure of a screw post according to claim 1, characterized in that, The top plate (4) is equipped with several push rods (42), which pass through the push plate (5) and the lower mold base (3) in sequence. Each of the push rods (42) is fitted with a return spring (43), one end of which abuts against the top of the push plate (5) and the other end of which abuts against the bottom of the lower mold base (3).

6. A novel ejection structure of a screw post according to claim 1, characterized in that, A number of guide posts (15) are installed on the base plate (1). The guide posts (15) pass through the top plate (4) and the push plate (5) in sequence, and their upper end face abuts against the lower end face of the lower mold base (3).

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