A mold structure having self retracting core

Abstract

A mold structure with self retracting core, comprising an upper and lower movable mold and fixed mold, the fixed mold is provided with a cavity, the rear part of the cavity is a forming area and the front part is provided with a core-pulling seat, the core-pulling seat is provided with a core-pulling block which can move along the front and rear directions, and a left core-pulling and a right core-pulling which are respectively located at the left side and the right side of the core-pulling block and slide along the left and right directions relative to the core-pulling seat; the movable mold is provided with a guide table which extends to the front part of the cavity, the guide table is provided with a third guide rail which gradually inclines forward from top to bottom, and the front end of the core-pulling block is slidably connected to the third guide rail. The above scheme realizes the quick demolding of the forming part of the left core-pulling and the right core-pulling relative to the hook structure during demolding by designing the movable left core-pulling and the right core-pulling, and effectively improves the situation that the two fixed forming parts in the prior art are easy to cause the hook structure to be torn off when separating from the hook structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of injection molds, in particular to a mold structure with self-retracting cores. BACKGROUND

[0002] An injection mold is a key tool for mass production of plastic or metal products, which is usually composed of a fixed mold and a movable mold and a pouring system. The fixed mold and the movable mold form a cavity therebetween, and the shape of the cavity corresponds to the shape of the product. During processing, the molten raw material is injected into the cavity under high pressure, and after cooling and forming, the product is taken out by demolding, thereby obtaining a product with stable quality.

[0003] For thin-walled products, the structural strength is often low after cooling and forming in the cavity due to the thin wall thickness, so core pulling is needed to assist demolding. Figure 11 As shown in the figure, part of the thin-walled product needs to process two hook structures distributed on the left and right sides of the side wall, and the hook parts of the two hook structures are opposite and symmetrical to each other. The existing scheme usually designs two forming parts on the core pulling structure corresponding to the hook structure. After the product is cooled and formed, the core pulling structure is pushed upward or downward, so that the two forming parts of the core pulling structure are separated from the hook structure. However, since the hook structure is also a thin-walled structure, during the upward or downward movement of the core pulling structure, the forming part and the hook structure have a large demolding resistance due to close fitting, which often causes the hook structure to be torn off by the core pulling structure, seriously affecting the yield of the product. SUMMARY

[0004] The purpose of the present application is to solve the problem in the prior art that when processing thin-walled products with hook structures, the forming part of the core pulling structure directly has a large demolding resistance due to close fitting, which often causes the hook structure to be torn off by the core pulling structure, seriously affecting the yield of the product.

[0005] To solve the above problems, the present application provides a mold structure with self-retracting cores, which comprises a movable mold and a fixed mold arranged in an upper and lower manner. The fixed mold is provided with a cavity facing the movable mold. The rear part of the cavity is a forming area, and the front part is provided with a core pulling seat. A push rod is arranged in the fixed mold for pushing the core pulling seat up and down. A core pulling block is arranged in the core pulling seat and can move in the front and rear directions. A left core pulling structure and a right core pulling structure are respectively arranged on the left side and the right side of the core pulling block. The left side of the rear part of the core pulling block is provided with a first guide rail, and the right side is provided with a second guide rail. The first guide rail is arranged obliquely to the right from front to back. The second guide rail is arranged obliquely to the left from front to back. The left core pulling structure and the right core pulling structure are respectively connected to the first guide rail and the second guide rail through sliding connection. The left core pulling structure and the right core pulling structure are slidably matched with the core pulling seat in the left and right directions. A forming part is arranged on the left side of one end of the left core pulling structure facing the forming area. A forming part is arranged on the right side of one end of the right core pulling structure facing the forming area.

[0006] The moving mold is provided with a guide platform extending to the front of the cavity, and the guide platform is provided with a third guide rail that gradually tilts forward from top to bottom. The front end of the core-pulling block is slidably connected to the third guide rail.

[0007] During demolding, as the moving mold moves upward away from the fixed mold, the guide platform moves upward, causing the core-pulling block to move forward by the third guide rail. Consequently, the left core-pulling block is moved to the right by the first guide rail, and the right core-pulling block is moved to the left by the second guide rail.

[0008] In the above solution, the forming area of ​​the cavity is the forming position of the product, and the rear side of the core-pulling seat corresponds to the outer wall of the product. The forming parts of the left and right core-pulling parts on the core-pulling seat achieve the forming of the two hook structures on the outer wall of the product. During demolding, as the moving mold moves upward, the core-pulling block drives the left and right core-pulling parts to move closer together, allowing the forming parts of the left and right core-pulling parts to move a small distance to directly detach from the hook structure. Then, the push rod pushes the core-pulling seat up, allowing the product to be removed. Compared with existing technologies, the above solution, by designing movable left and right core-pulling parts, achieves rapid demolding of the left and right core-pulling parts relative to the hook structure during demolding. This effectively improves the situation in existing technologies where the fixed forming parts easily break when detaching from the hook structure, thus possessing better practicality.

[0009] In an improved embodiment, the core-pulling seat has a guide hole extending in the front-rear direction. A limiting protrusion ring is provided at the front of the guide hole. The front of the core-pulling block is slidably inserted into the inner hole of the limiting protrusion ring, and its rear side corresponds to the rear end of the guide hole. The left and right core-pulling blocks are both located at the rear of the guide hole, and the rear sides of the left and right core-pulling blocks are flush with the rear side of the core-pulling block. The front ends of the left and right core-pulling blocks slide against the rear side of the limiting protrusion ring, thereby guiding the core-pulling block in the front-rear direction through the inner hole of the limiting protrusion ring. At the same time, the sliding abutment action of the limiting protrusion ring on the front ends of the left and right core-pulling blocks limits the movement direction of the left and right core-pulling blocks relative to the core-pulling seat to the left-right direction. The structure is compact and the operation is stable.

[0010] In an improved embodiment, the rear end of the guide hole is rectangular, and a scraper is provided on the lower edge of the rear end of the guide hole. When the core-pulling block drives the left and right core-pulling blocks to approach each other, the front sides of the left and right core-pulling blocks will compress the outer wall of the product, causing excess material to protrude at the corresponding position on the outer wall of the product. Therefore, by providing a scraper on the lower edge of the front end of the guide hole, when the push rod drives the core-pulling seat to rise in the final stage, the scraper can scrape off the excess material protrusion, ensuring the flatness of the outer wall of the product.

[0011] In an improved scheme, the rear part of the lower side wall of the guide hole is provided with a downward penetrating waste hole, so that the excess material scraped off by the scraping blade can be discharged from the waste hole and fall back into the cavity of the fixed mold, avoiding the accumulation of excess material in the guide hole.

[0012] In an improved scheme, the left side surface of the rear part of the core-pulling block is inclined to the right from front to back, and the right side surface is inclined to the left from front to back, the first guide rail is arranged in parallel to the left side surface of the rear part of the core-pulling block, and the second guide rail is arranged in parallel to the right side surface of the rear part of the core-pulling block.

[0013] In an improved scheme, the front side of the core-pulling seat is provided with a vertically extending guide groove, and the guide table is slidingly fitted into the guide groove. Since the guide table will be subjected to a larger deflection torque when the third guide rail drives the core-pulling block, the guide groove is arranged on the front side of the core-pulling seat to guide the guide table, thereby improving the stability of the guide table during movement.

[0014] In an improved scheme, the lifting plate and the lifting driving member are further included, the lifting driving member is arranged vertically on one side of the fixed mold, the lifting plate is located below the fixed mold and is driven to lift by the lifting driving member, the push rod is at least two, the lower end of the push rod is connected with the lifting plate, and the upper end of the push rod is connected with the core-pulling seat, so that the lifting driving member cooperates with the lifting plate to drive the lifting of the plurality of push rods, thereby realizing the more stable lifting drive of the core-pulling seat. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a schematic diagram of a mold structure with self-shrinking core-pulling;

[0016] Figure 2 It is a schematic diagram of a mold structure with self-shrinking core-pulling from the front view;

[0017] Figure 3 It is a schematic diagram of a mold structure with self-shrinking core-pulling from the side view; Figure 2 It is a schematic diagram of a mold structure with self-shrinking core-pulling along the A-A section line;

[0018] Figure 4 It is a schematic diagram of a mold structure with self-shrinking core-pulling along the B-B section line; Figure 3 It is a schematic diagram of a mold structure with self-shrinking core-pulling along the B-B section line;

[0019] Figure 5 It is a schematic diagram of a mold structure with self-shrinking core-pulling along the C region; Figure 3 It is a schematic diagram of a mold structure with self-shrinking core-pulling along the C region;

[0020] Figure 6 It is a schematic diagram of a mold structure with self-shrinking core-pulling after the fixed mold is hidden;

[0021] Figure 7 It is a schematic diagram of a mold structure with self-shrinking core-pulling after the fixed mold and the movable mold are hidden; It is a schematic diagram of a mold structure with self-shrinking core-pulling after the fixed mold and the movable mold are hidden;

[0022] Figure 8 Fig. 1 is a schematic view of the back side of a core-pulling base of a mold structure with self-retracting cores;

[0023] Figure 9 Fig. 2 is a schematic view of a core-pulling block, a left core and a right core of a mold structure with self-retracting cores;

[0024] Figure 10 Fig. 3 is a schematic view of a core-pulling block of a mold structure with self-retracting cores;

[0025] Figure 11 Fig. 4 is a schematic view of a product.

[0026] Fig. 5 is a schematic view of the core-pulling base of the mold structure with self-retracting cores.

[0027] 1, moving mold; 11, guide table; 12, third guide rail; 2, fixed mold; 21, cavity; 21a, forming area; 3, push rod; 4, core-pulling base; 41, guide hole; 42, limiting convex ring; 43, scraping blade; 44, waste hole; 45, guide groove; 5, core-pulling block; 51, first guide rail; 52, second guide rail; 61, left core; 62, right core; 63, forming part; 7, lifting driving part; 71, lifting plate; 8, hook structure. DETAILED DESCRIPTION

[0028] It should be understood by those skilled in the art that the following embodiments are only used to explain the technical principles of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments as needed in order to adapt to specific application occasions.

[0029] In the description of the following embodiments, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0030] In the embodiments of the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0031] The application will be described in further detail below with reference to the drawings and specific embodiments.

[0032] Please refer to Figures 1-11 The embodiment of the application provides a mold structure with self retracting core, which comprises a movable mold 1 and a fixed mold 2 arranged in a top-down manner, the fixed mold 2 is provided with a cavity 21 facing the movable mold 1, the rear part of the cavity 21 is a forming area 21a and the front part is provided with a core-pulling base 4, the fixed mold 2 is provided with a push rod 3 for pushing the core-pulling base 4 to move up and down, the core-pulling base 4 is provided with a core-pulling block 5 which can move in the front-rear direction, and a left core-pulling block 61 and a right core-pulling block 62 are respectively arranged on the left side and the right side of the core-pulling block 5, the left side of the rear part of the core-pulling block 5 is provided with a first guide rail 51 and the right side is provided with a second guide rail 52, the first guide rail 51 is arranged to be inclined to the right from front to back, the second guide rail 52 is arranged to be inclined to the left from front to back, the left core-pulling block 61 and the right core-pulling block 62 are respectively connected to the first guide rail 51 and the second guide rail 52 in a sliding manner, and the left core-pulling block 61 and the right core-pulling block 62 are slidably matched with the core-pulling base 4 in the left-right direction, the left side of one end of the left core-pulling block 61 facing the forming area 21a is provided with a forming part 63, and the right side of one end of the right core-pulling block 62 facing the forming area 21a is provided with a forming part 63.

[0033] The movable mold 1 is provided with a guide table 11 extending to the front part of the cavity 21, the guide table 11 is provided with a third guide rail 12 which is gradually inclined forward from top to bottom, and the front end of the core-pulling block 5 is connected to the third guide rail 12 in a sliding manner.

[0034] When demolding, with the movable mold 1 moving upward and away from the fixed mold 2, the guide table 11 moves upward, so that the core-pulling block 5 is driven by the third guide rail 12 to move forward, and then the left core-pulling block 61 is driven by the first guide rail 51 to move rightward, and the right core-pulling block 62 is driven by the second guide rail 52 to move leftward.

[0035] In the above scheme, the forming area 21a of the cavity 21 is the forming position of the product, the rear side of the core-pulling base 4 corresponds to the outer side wall of the product, and the forming parts 63 of the left core-pulling block 61 and the right core-pulling block 62 on the core-pulling base 4 are used to realize the forming processing of the two hook structures 8 of the outer side wall of the product. Figure 3 As shown in the figure, since the forming parts 63 of the left core-pulling block 61 and the right core-pulling block 62 need to correspond to the hook structures 8, the forming part 63 of the left core-pulling block 61 is a groove opened on the left side of the rear end of the left core-pulling block 61, and the forming part 63 of the right core-pulling block 62 is a groove opened on the right side of the rear end of the right core-pulling block 62. It should be understood that the forming part 63 can also have other shapes according to needs, and the design does not limit this.

[0036] When demolding, as the movable mold 1 moves upward, the core pulling block 5 drives the left core pulling block 61 and the right core pulling block 62 to move close to each other, so that the forming portions 63 of the left core pulling block 61 and the right core pulling block 62 can directly separate from the hook structure 8 by moving a small distance, and then the core pulling block 4 is lifted by the push rod 3, so that the product can be taken out. Compared with the prior art, the above scheme realizes the quick demolding of the forming portions 63 of the left core pulling block 61 and the right core pulling block 62 relative to the hook structure 8 during demolding by designing the movable left core pulling block 61 and the right core pulling block 62, effectively improves the situation that the two fixed forming portions 63 in the prior art are easily torn off from the hook structure 8, and has good practicability.

[0037] In combination Figure 3 As shown in the embodiment, the core pulling block 4 is provided with a guide hole 41 penetrating in the front-rear direction, the guide hole 41 is located in the middle of the core pulling block 4, the front part of the guide hole 41 is provided with a limiting convex ring 42, the front part of the core pulling block 5 is slidingly inserted into the inner hole of the limiting convex ring 42 and the rear side corresponds to the rear end of the guide hole 41, the left core pulling block 61 and the right core pulling block 62 are located in the rear part of the guide hole 41, and the rear sides of the left core pulling block 61 and the right core pulling block 62 are flush with the rear side of the core pulling block 5, the front ends of the left core pulling block 61 and the right core pulling block 62 slidingly abut to the rear side of the limiting convex ring 42, so as to realize the front-rear direction guidance of the core pulling block 5 through the inner hole of the limiting convex ring 42, and through the sliding abutting action of the limiting convex ring 42 to the front ends of the left core pulling block 61 and the right core pulling block 62, the left core pulling block 61 and the right core pulling block 62 cannot move forward and backward, but can only move left and right relative to the core pulling block 4, so the structure is compact and the operation is stable. In addition, the rear sides of the left core pulling block 61 and the right core pulling block 62 are flush with the rear side of the core pulling block 5, which can make the product outer side wall in a flat state during forming; if the product outer side wall does not need to be in a flat state, the rear sides of the left core pulling block 61 and the right core pulling block 62 do not need to be flush with the rear side of the core pulling block 5, and this way also belongs to the protection scope of the embodiment.

[0038] In combination Figure 4 And Figure 8 As an optimization scheme of the embodiment, the rear end of the guide hole 41 is rectangular, and the lower side edge of the rear end of the guide hole 41 is provided with a scraping blade 43, which is a relatively sharp horizontal edge and has a higher hardness than the core pulling block 5. After the core pulling block 5 drives the left core pulling block 61 and the right core pulling block 62 to move close to each other, the rear sides of the left core pulling block 61 and the right core pulling block 62 will extrude the product outer side wall, causing the corresponding position of the product outer side wall to form a excess material protrusion. Therefore, by providing the scraping blade 43 on the lower side edge of the rear end of the guide hole 41, when the core pulling block 4 is lifted by the push rod 3 in the last stage, the scraping blade 43 can scrape the excess material protrusion, ensuring the flatness of the product outer side wall.

[0039] Further, as Figure 4As shown, the rear part of the lower side wall of the guide hole 41 is provided with a waste discharge hole 44 penetrating downward to the bottom surface of the core-pulling base 4, so that the excess material scraped off by the scraping blade 43 can be discharged from the waste discharge hole 44 and fall back into the cavity of the fixed mold, avoiding the accumulation of excess material in the guide hole 41.

[0040] As shown in the drawings, Figure 5 In the present embodiment, the left side surface of the rear part of the core-pulling block 5 is inclined to the right from front to back, and the right side surface is inclined to the left from front to back, so that the rear part of the core-pulling block 5 forms a shape similar to a trapezoid or a cone, the first guide rail 51 is arranged in parallel on the left side surface of the rear part of the core-pulling block 5, and the second guide rail 52 is arranged in parallel on the right side surface of the rear part of the core-pulling block 5. In addition, the first guide rail 51 and the second guide rail 52 are both dovetail guide rails, so as to ensure more stable sliding fit between the first guide rail 51 and the left core-pulling block 61, and between the second guide rail 52 and the right core-pulling block 62.

[0041] As shown in the drawings, Figure 7 As an improvement of the present embodiment, the front side of the core-pulling base 4 is provided with a vertically extending guide groove 45, and the guide table 11 is slidingly fitted into the guide groove 45. Since the guide table 11 will be subjected to a large deflection torque when the third guide rail 12 drives the core-pulling block 5, the guide groove 45 is arranged on the front side of the core-pulling base 4 to guide the guide table 11, thereby improving the stability of the guide table 11 during movement.

[0042] As another improvement of the present embodiment, a lifting plate 71 and a lifting driving member 7 are further included, the lifting driving member 7 is preferably an oil cylinder and is arranged vertically on one side of the fixed mold 2, the lifting plate 71 is located below the fixed mold 2 and is driven to lift by the lifting driving member 7, the push rod 3 is at least two and the lower end of the push rod 3 is connected with the lifting plate 71, and the upper end of the push rod 3 is connected with the core-pulling base 4, so that the lifting driving member 7 drives the lifting plate 71 to drive the plurality of push rods 3 to lift, thereby realizing more stable lifting drive of the core-pulling base 4.

[0043] It should be noted that in the description of the present application, the terms indicating the direction or positional relationship such as "inner", "outer" and the like are based on the direction or positional relationship shown in the drawings, which is merely for the convenience of description, and does not indicate or imply that the device or member must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application; all directional indications (such as up, down, left, right, front, back, inner, outer) are only used to explain the relative positional relationship, movement condition and the like between the components in a certain specific posture, and if the specific posture changes, the directional indications will also change accordingly.

[0044] In the description of the application, the description of the terms "one embodiment", "some embodiments", "in this embodiment", "specific example", or "some examples" and the like means that the specific features, mechanisms, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the application. In the description, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0045] The above description is merely a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A mold structure having a self- retracting core, characterized by, The die set comprises an upper and lower movable die and a fixed die, the fixed die is provided with a cavity towards the movable die, the rear part of the cavity is a forming area and the front part is provided with a core-pulling base, the fixed die is provided with a push rod for pushing the core-pulling base to move up and down, the core-pulling base is provided with a core-pulling block which can move in the front-rear direction, and a left core-pulling and a right core-pulling are respectively arranged on the left side and the right side of the core-pulling block, the left side of the rear part of the core-pulling block is provided with a first guide rail which is inclined to the right from front to back, the right side of the rear part of the core-pulling block is provided with a second guide rail which is inclined to the left from front to back, the left core-pulling and the right core-pulling are respectively connected to the first guide rail and the second guide rail by sliding, and the left core-pulling and the right core-pulling are slidably matched with the core-pulling base in the left-right direction, the left side of one end of the left core-pulling towards the forming area is provided with a forming part, and the right side of one end of the right core-pulling towards the forming area is provided with a forming part. The movable die is provided with a guide table extending to the front part of the cavity, the guide table is provided with a third guide rail which is gradually inclined forward from top to bottom, and the front end of the core-pulling block is connected to the third guide rail by sliding. When the mold is demolded, as the movable die moves upward away from the fixed die, the guide table moves upward, so that the core-pulling block is driven by the third guide rail to move forward, the left core-pulling is driven by the first guide rail to move right, and the right core-pulling is driven by the second guide rail to move left.

2. The mold structure having self- retracting core according to claim 1, wherein, The core-pulling base is provided with a guide hole which penetrates in the front-rear direction, the front part of the guide hole is provided with a limiting convex ring, the front part of the core-pulling block is inserted into the inner hole of the limiting convex ring and the rear side corresponds to the rear end of the guide hole, the left core-pulling and the right core-pulling are both located in the rear part of the guide hole, and the rear sides of the left core-pulling and the right core-pulling are flush with the rear side of the core-pulling block, and the front ends of the left core-pulling and the right core-pulling are slidably abutted to the rear side of the limiting convex ring.

3. The mold structure having self- retracting core according to claim 2, wherein, The rear end of the guide hole is rectangular, and the lower side edge of the rear end of the guide hole is provided with a scraping blade.

4. The mold structure having self- retracting core according to claim 3, wherein The rear part of the lower side wall of the guide hole is provided with a waste discharge hole which penetrates downward.

5. A mould structure with self- retracting cores according to any one of claims 2-4, characterised in that The left side surface of the rear part of the core-pulling block is inclined to the right from front to back, and the right side surface of the rear part of the core-pulling block is inclined to the left from front to back, the first guide rail is arranged in parallel on the left side surface of the rear part of the core-pulling block, and the second guide rail is arranged in parallel on the right side surface of the rear part of the core-pulling block.

6. The mold structure having self- retracting core according to claim 1, wherein, The front side of the core-pulling base is provided with a guide groove which extends in the vertical direction, and the guide table is slidably matched with the guide groove.

7. A mold structure having self- retracting cores according to claim 1 or 6, characterized in that, Further comprising a lifting plate and a lifting driving member, the lifting driving member is arranged in the vertical direction on one side of the fixed die, the lifting plate is located below the fixed die and is driven by the lifting driving member to move up and down, the push rod is at least two, and the lower end of the push rod is connected with the lifting plate, and the upper end of the push rod is connected with the core-pulling base.

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