Ejection structure of thin-walled inverted-dowel product

Abstract

The utility model discloses a kind of ejection structure of thin-wall inverted product, it is related to mould technical field, including separable butt joint's front mould and back mould, the push plate of movable connection in back mould is equipped between the front mould and back mould, elastic component is equipped between the push plate and back mould;The elastic component can drive push plate to move relative to back mould when the front mould and back mould separate, to form the first gap for product inverted structure deformation;The utility model forms first gap by setting push plate and elastic component, cooperates the linkage structure of forming insert, ejector pin and ejector pin plate, can provide sufficient deformation space for product inverted structure in stripping process, moves and accurately applies ejection force by step, both avoid the deformation or cracking of thin-wall product due to stress concentration, and simplify mould structure, improve stripping stability and product forming quality.

Description

Technical Field

[0001] This utility model relates to the field of mold technology, specifically to an ejection structure for a thin-walled undercut product. Background Technology

[0002] In the injection molding of thin-walled products with undercuts, the core challenge in the demolding process lies in how to release the interlocking constraint between the undercut structure and the mold forming surface while ensuring the integrity of the product. Because these products have thin walls and the material itself has a certain degree of elastic deformation capability, the industry often adopts a demolding approach based on the plastic deformation of the material. This involves utilizing the product's own elasticity or plastic deformation to achieve undercut release. With a reasonable structural design, this method can simplify mold complexity.

[0003] However, existing structures that adopt similar deformation demolding approaches still have many shortcomings: in some structures, the deformation space in the undercut area of ​​the product is insufficient or the timing of the deformation is inappropriate, resulting in concentrated stress on the product during demolding, which can easily lead to permanent deformation or cracking; in other structures, the linkage and coordination precision of various moving parts is insufficient, which can easily cause problems such as motion jamming or poor synchronization during the deformation process of the product, which not only affects the demolding efficiency, but may also cause the product to be scrapped due to excessive local stress.

[0004] In addition, how to accurately control the degree of product deformation during the deformation demolding process, avoid exceeding the plastic limit of the material, and at the same time ensure the movement stability and service life of each component of the mold, remains a key issue that needs to be optimized in the existing technology. Utility Model Content

[0005] To overcome the shortcomings mentioned above, this utility model aims to provide a technical solution that can solve the above problems.

[0006] An ejection structure for a thin-walled undercut product includes a separable and dockable front mold and a rear mold, wherein a push plate is movably connected to the rear mold between the front mold and the rear mold, and an elastic component is provided between the push plate and the rear mold. The elastic component can drive the push plate to move relative to the rear mold when the front mold and the rear mold separate, so as to form a first gap for the deformation of the product's undercut structure.

[0007] As a further embodiment of this utility model: an insert seat is provided between the push plate and the rear mold and is fixedly installed in the rear mold. A molding insert is slidably connected in the insert seat. An ejector pin is slidably inserted in the molding insert. The lower end of the ejector pin is connected to an ejector plate that is movablely engaged with the rear mold. The top of the molding insert is provided with a first product contouring part, and the top of the ejector pin is provided with a second product contouring part. The top of the first product contouring part and the bottom of the second product contouring part form a limiting contact. The side of the first product contouring part, together with the top of the insert seat and the inner side wall of the push plate, form a cavity for molding the undercut structure of the product.

[0008] As a further embodiment of this utility model: when the first gap is formed, the push plate drives the product to move synchronously through the contact between the inner wall of the cavity and the outer wall of the product. The product drives the molding insert and ejector pin to slide relative to the insert seat away from the rear mold through the interlocking action of its undercut structure and the first product contour part, so that a clearance space is formed between the root of the undercut structure of the product and the top surface of the insert seat for the elastic deformation of the undercut structure of the product.

[0009] As a further embodiment of this utility model: the elastic component includes a first spring and a stop screw; The two ends of the first spring abut against the push plate and the rear mold respectively. The screw end of the plug screw passes through the push plate and is threadedly connected to the rear mold. The push plate is provided with a stepped hole for the head of the plug screw to slide.

[0010] As a further embodiment of this utility model: the lower end of the ejector pin is a connecting end that cooperates with the ejector pin plate, and the connecting end has a first connecting end that abuts against the upper limit of the ejector pin plate and a second connecting end that abuts against the lower limit of the ejector pin plate; The second connecting end and the lower end of the ejector plate have a second gap corresponding to the first gap.

[0011] As a further embodiment of this utility model: a second spring sleeved on the ejector plate and the molding insert is provided between the ejector plate and the ejector pin.

[0012] As a further embodiment of this utility model: the side end of the molded insert extends to form an abutment portion that engages with the insert seat for limiting and abutting.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: This invention, by setting a first gap between the push plate and the elastic component, and coordinating the linkage structure of the molding insert, ejector pin and ejector plate, can provide sufficient deformation space for the undercut structure of the product during demolding. By driving the product to move step by step and applying ejection force precisely, it avoids deformation or cracking of thin-walled products due to concentrated force, simplifies the mold structure, and improves demolding stability and product molding quality.

[0014] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the structure of the elastic component in this utility model; Figure 3 This is a structural schematic diagram of the connection state between the push plate and the rear mold in this utility model; Figure 4 yes Figure 3 Enlarged structural diagram at point A; Figure 5 This is a structural diagram of the push plate and the rear mold in the separated state in this utility model.

[0017] The reference numerals and names in the figure are as follows: 1. Front mold; 2. Rear mold; 3. Ejector plate; 4. First gap; 5. Insert holder; 6. Molding insert; 7. Ejector pin; 8. Ejector plate; 9. First product contour part; 10. Second product contour part; 11. Clearance space; 12. First spring; 13. Plug screw; 14. Step hole; 15. First connecting end; 16. Second connecting end; 17. Second gap; 18. Second spring; 19. Abutment part; 20. Cavity; 21. Undercut structure. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Please see Figure 1-5 In this embodiment of the invention, an ejection structure for a thin-walled undercut product is provided to facilitate the demolding of the thin-walled undercut product.

[0020] The ejection structure includes a front mold 1 and a rear mold 2, which can be separated and connected along the parting surface. A push plate 3 is provided between the front mold 1 and the rear mold 2, and the push plate 3 is movably connected to the rear mold 2. An elastic component is assembled between the push plate 3 and the rear mold 2. When the mold opens and the front mold 1 and the rear mold 2 separate, the elastic component drives the push plate 3 to move relative to the rear mold 2, thereby forming a first gap 4 between the push plate 3 and the rear mold 2. This first gap 4 provides a basic space for the deformation of the subsequent undercut structure 21 of the product.

[0021] The elastic component specifically includes a first spring 12 and a stop screw 13. The first spring 12 is arranged circumferentially around the push plate 3, with its two ends abutting against the rear end face of the push plate 3 and the front end face of the rear mold 2, respectively, to provide a continuous elastic force to drive the push plate 3 away from the rear mold 2. The screw end of the stop screw 13 passes through the push plate 3 and is threadedly connected to the rear mold 2. The push plate 3 is provided with a stepped hole 14 for the head of the stop screw 13 to slide. Through the cooperation between the head of the stop screw 13 and the stepped hole 14, it can both guide the movement of the push plate 3 and limit the maximum travel of the push plate 3, ensuring the dimensional stability of the first gap 4.

[0022] Between the push plate 3 and the rear mold 2, an insert seat 5 is fixedly installed on the rear mold 2, and a molding insert 6 is slidably connected axially inside the insert seat 5. The side end of the molding insert 6 extends to form an abutment portion 19. When the molding insert 6 slides relative to the insert seat 5 to a preset position, the abutment portion 19 can form a limiting abutment with the corresponding end face of the insert seat 5, thereby limiting excessive sliding of the molding insert 6 and ensuring the stability of the movement. An ejector pin 7 is slidably inserted axially inside the molding insert 6. The lower end of the ejector pin 7 is connected to an ejector plate 8, which is axially movable with the rear mold 2 and can reciprocate relative to the rear mold 2.

[0023] The lower end of the ejector pin 7 is a connecting end that mates with the ejector plate 8. This connecting end has a first connecting end 15 and a second connecting end 16. The first connecting end 15 is located above and can form a limiting abutment with the upper end face of the ejector plate 8. The second connecting end 16 is located below and can form a limiting abutment with the lower end face of the ejector plate 8. In the initial mold-closed state, there is a second gap 17 between the second connecting end 16 and the lower end face of the ejector plate 8. The size of the second gap 17 corresponds to the preset size of the first gap 4. In addition, a second spring 18 is provided between the ejector plate 8 and the molding insert 6. The second spring 18 is sleeved on the outside of the ejector pin 7, and its two ends abut against the upper end face of the ejector plate 8 and the rear end face of the molding insert 6, respectively, to provide elastic restoring force between the ejector pin 7 and the molding insert 6.

[0024] In one embodiment, the second gap 17 does not necessarily need to correspond to the size of the first gap 4. It is only necessary to ensure that the ejector pin 7 can slide relative to the ejector plate 8 during the process of the first gap 4 being generated between the push plate 3 and the rear mold 2, so as to ensure that the ejector plate 8 does not interfere with the subsequent driving action of the external power.

[0025] The top of the molding insert 6 is provided with a first product contouring part 9, and the top of the ejector pin 7 is provided with a second product contouring part 10. The top surface of the first product contouring part 9 and the bottom surface of the second product contouring part 10 form a limiting contact to ensure the positional accuracy of the two during molding. The side surface of the first product contouring part 9, together with the top surface of the insert base 5 and the inner sidewall of the push plate 3, form a cavity 20. The contour of the cavity 20 is adapted to the shape of the product undercut structure 21 for precise molding of the product undercut structure 21.

[0026] When the mold opens and the front mold 1 separates from the rear mold 2, the elastic component drives the push plate 3 to move and form the first gap 4. During this process, the push plate 3 abuts against the outer wall of the product through the inner wall of the cavity 20, thereby driving the product to move synchronously. When the product moves, through the cooperation (engagement) between its undercut structure 21 and the first product contouring part 9, the molding insert 6 and the ejector pin 7 (because the top surface of the first product contouring part 9 and the bottom surface of the second product contouring part 10 form a limiting abutment, the ejector pin 7 will move along with it) slide away from the insert seat 5 away from the rear mold 2. At this time, due to the existence of the second gap 17, the ejector pin 7 first moves upward relative to the ejector plate 8. When the abutting part 19 of the molding insert 6 abuts against the insert seat 5, the molding insert 6 stops sliding. At this time, a clearance space 11 is formed between the root of the undercut structure 21 and the top surface of the insert seat 5. This clearance space 11 provides sufficient space for the elastic deformation of the undercut structure 21.

[0027] When further ejection of the product is required, the ejector plate 8 is driven upward by external power. After the upper end face of the ejector plate 8 abuts against the first connecting end 15 of the ejector pin 7, the ejector pin 7 slides upward relative to the molding insert 6. The second product contouring part 10 at the top of the ejector pin 7 pushes the product, causing the undercut structure 21 of the product to undergo elastic deformation within the clearance space 11, gradually separating from the first product contouring part 9, and finally achieving complete separation of the product from the mold, thus completing the demolding process.

[0028] In summary, by setting the push plate 3 and the elastic component to form a first gap 4, and cooperating with the linkage structure of the molding insert 6, the ejector pin 7 and the ejector plate 8, this utility model can provide sufficient deformation space for the undercut structure 21 of the product during the demolding process. By driving the product to move step by step and applying the ejection force precisely, it can avoid the deformation or cracking of thin-walled products caused by concentrated force, simplify the mold structure, and improve the demolding stability and product molding quality.

[0029] 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 exemplary 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.

Claims

1. An ejection structure for a thin-walled inverted product, characterized in that, It includes a separable and dockable front mold and a rear mold, wherein a push plate is provided between the front mold and the rear mold and is movably connected to the rear mold, and an elastic component is provided between the push plate and the rear mold; The elastic component can drive the push plate to move relative to the rear mold when the front mold and the rear mold separate, so as to form a first gap for the deformation of the product's undercut structure.

2. The ejection structure of a thin-walled undercut product according to claim 1, characterized in that, An insert seat is fixedly installed in the rear mold between the push plate and the rear mold. A molding insert is slidably connected in the insert seat. An ejector pin is slidably inserted in the molding insert. The lower end of the ejector pin is connected to an ejector plate that is movable and cooperates with the rear mold. The top of the molding insert is provided with a first product contouring part, and the top of the ejector pin is provided with a second product contouring part. The top of the first product contouring part and the bottom of the second product contouring part form a limiting contact. The side of the first product contouring part, together with the top of the insert seat and the inner side wall of the push plate, form a cavity for molding the undercut structure of the product.

3. The ejection structure of a thin-walled undercut product according to claim 2, characterized in that, When the first gap is formed, the push plate drives the product to move synchronously through the contact between the inner wall of the cavity and the outer wall of the product. The product drives the molding insert and ejector pin to slide away from the insert seat relative to the insert seat through the interlocking action of its undercut structure and the first product contour part, so that a clearance space is formed between the root of the undercut structure of the product and the top surface of the insert seat for the elastic deformation of the undercut structure of the product.

4. The ejection structure of a thin-walled undercut product according to any one of claims 1-3, characterized in that, The elastic component includes a first spring and a stop screw; The two ends of the first spring abut against the push plate and the rear mold respectively. The screw end of the plug screw passes through the push plate and is threadedly connected to the rear mold. The push plate is provided with a stepped hole for the head of the plug screw to slide.

5. The ejection structure of a thin-walled undercut product according to any one of claims 1-3, characterized in that, The lower end of the ejector pin is a connecting end that mates with the ejector pin plate. The connecting end has a first connecting end that abuts against the upper limit of the ejector pin plate and a second connecting end that abuts against the lower limit of the ejector pin plate. The second connecting end and the lower end of the ejector plate have a second gap corresponding to the first gap.

6. The ejection structure of a thin-walled undercut product according to claim 5, characterized in that, A second spring, sleeved on the ejector plate, is provided between the ejector plate and the molding insert.

7. The ejection structure of a thin-walled undercut product according to claim 5, characterized in that, The side end of the molded insert extends to form an abutment portion that engages with the insert seat.

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