CN116100769A

CN116100769A - Ejection mechanism of die

Info

Publication number: CN116100769A
Application number: CN202310125708.9A
Authority: CN
Inventors: 虞伟炳; 李金国; 傅建华; 姚震
Original assignee: Zhejiang Saihao Industrial Co ltd
Current assignee: Zhejiang Saihao Industrial Co ltd
Priority date: 2023-01-21
Filing date: 2023-01-21
Publication date: 2023-05-12

Abstract

The invention provides an ejection mechanism of a mold, and belongs to the technical field of injection molds. It has solved the problem that production efficiency is low. The movable die comprises a top plate positioned below a movable die, a first ejector rod and a second ejector rod which are all arranged in the movable die in a penetrating way, wherein the lower end of the first ejector rod is fixed with the top plate, the upper end of the second ejector rod is fixed with a top block embedded in the top of the movable die, a linkage structure which enables the top plate to drive the second ejector rod to move upwards synchronously is arranged between the lower end of the second ejector rod and the top plate, the outer side of the second ejector rod is provided with a propping part which can prop against the movable die to enable the top plate to release linkage with the second ejector rod, the top block is provided with a through hole, a core rod and a top spring are arranged in the through hole, one end of the core rod is positioned at a notch of the top block and the top spring acts on the core rod in a direction away from the notch, and one side wall of the movable die in the embedded position of the top block is obliquely arranged, and the other end of the core rod props against the side wall. It has the advantages of improving the production efficiency of the product, etc.

Description

Ejection mechanism of die

Technical Field

The invention belongs to the technical field of injection molds, and relates to an ejection mechanism of a mold.

Background

The molding compound injection mold is a molding mold which is most commonly applied in the production of thermoplastic plastic products, and comprises a fixed mold and a movable mold arranged below the fixed mold, wherein a cavity is formed when the fixed mold and the movable mold are closed, a product with the same shape as the cavity can be molded after melt plastic is injected into the cavity, the movable mold and the fixed mold are separated to complete mold opening after the product is molded, and the product is generally adsorbed on the side of the movable mold after the mold is opened. Along with the popularization of the mechanical arm, the automation degree of the injection molding industry is higher and higher, and therefore, the automatic ejection of products and the streamline production of automatic picking of the mechanical arm are formed.

The automatic ejection of the product depends on arranging an ejection mechanism on a die, particularly on the side of a movable die, for the product with a regular and flat shape, the arranged ejection mechanism has a relatively simple structure and generally comprises a top plate which is positioned below the movable die and can move upwards driven by a hydraulic cylinder and a plurality of ejector rods which penetrate through the movable die and are fixed with the top plate at the lower end, each ejector rod is driven by the top plate to move upwards so as to automatically eject the product, and further, in order to ensure stable ejection of the product, an ejector block (the top surface of the ejector block is a cavity surface which forms a cavity together with the top surface of the movable die) is embedded at the top of the movable die, then some ejector rods are fixed with the ejector block, the ejector rods which directly act on the product are called first ejector rods and the ejector rods which are fixed with the ejector blocks are called second ejector rods for convenience in distinguishing, namely the top plate simultaneously carries the first ejector rods and the second ejector rods to move upwards. However, for products that are not regular in shape and require forming a protruding portion toward one side of the movable mold, a notch needs to be provided on one side of the ejector block to be matched with the side wall of the movable mold where the ejector block is embedded to form a forming groove that is communicated with the cavity, so that molten plastic is injected into the cavity and is also injected into the forming groove to form the protruding portion.

According to practical requirements, the above-mentioned protruding portion is sometimes required to be provided with a hole site, and the most ideal mode is that the product is directly provided with the hole site after injection molding, but because the size of the protruding portion is relatively small and the position is relatively special, core-pulling demolding at the hole site is difficult to realize in practice by adopting a traditional mode of obliquely ejecting core-pulling mechanism for a sliding block on a movable die, so that the required hole site is generally processed on the protruding portion of the product after the product is added, and the problem of relatively low production efficiency exists.

Disclosure of Invention

The invention aims at solving the problems existing in the prior art, and provides an ejection mechanism of a die, which solves the problem of low production efficiency.

The aim of the invention can be achieved by the following technical scheme:

the ejection mechanism of the die comprises a top plate positioned below the movable die, and a first ejector rod and a second ejector rod which are respectively arranged in the movable die in a penetrating way, wherein the lower end of the first ejector rod is fixed with the top plate, the upper end of the second ejector rod is fixed with an ejector block embedded in the top of the movable die and provided with a notch on one side, a linkage structure which enables the top plate to drive the second ejector rod to move upwards synchronously is arranged between the lower end of the second ejector rod and the top plate, and an abutting part which can abut against the movable die to enable the top plate to release linkage with the second ejector rod.

The ejection mechanism is characterized in that a through hole is formed in the ejector block, a core rod is arranged in the through hole, one end of the core rod is abutted against one side wall of a movable die in the embedded position of the ejector block, and the other end of the core rod extends out of the through hole and is positioned at a notch of the ejector block, so that when melt plastics are injected into the die, the part of a molded product, which is reversely buckled at the notch, can be directly provided with a hole by means of the existence of one end of the core rod, which extends out of the notch of the ejector block. And a jacking spring acting on the core rod in a direction away from the notch is further arranged in the through hole, a side wall of the movable mould which is abutted against one end of the core rod in the embedded position of the jacking block is obliquely arranged, and a gap for the core rod to move in a direction away from the notch is formed between the jacking block and the side wall in the process of driving the jacking block to move upwards until the abutting part abuts against the movable mould (namely, in a first ejection process of a product), so that the core rod can move upwards along with the jacking block and is larger and larger along with the continuous upward movement of the jacking block, and the core rod can move continuously in a direction away from the notch under the action of the jacking spring to automatically finish the separation of a part of the product back-off at the notch of the jacking block, namely, the core rod is separated from the product after the primary ejection of the product is finished, so that the product can still smoothly finish the normal separation of the part of the product back-off at the notch of the jacking block during the secondary ejection. Through the arrangement, the product with holes on the back-off part can be directly produced by the die while the product can be normally ejected, and the holes do not need to be additionally machined after the injection molding of the product, so that the production efficiency of the product is improved.

In the ejection mechanism of the die, the through hole is a step hole, the smaller part of the through hole is communicated with the notch, the core bar is provided with a head part positioned in the larger part of the through hole and a rod part penetrating out of the smaller part of the through hole, the ejection spring is sleeved outside the rod part positioned in the larger part of the through hole, and two ends of the ejection spring respectively lean against the step surfaces in the head part and the through hole.

The core rod is mainly used for passing through the rod part to enable the formed product to be reversely buckled on the ejector block to be provided with a required hole site, the ejector spring is sleeved outside the rod part positioned in the larger part of the through hole, two ends of the ejector spring respectively lean against the head of the core rod and the step surface in the through hole, so that the elastic force of the ejector spring acts on the core rod in the direction that one end of the core rod positioned at the notch of the ejector block is retracted into the through hole, and when the head of the core rod is separated from the side wall of the movable die where the ejector block is embedded along with ejection of one section of the product, the automatic separation of the core rod and the product can be realized by virtue of the ejector spring, and therefore, the die can directly produce the product with the hole on the reversely buckled part by using the core rod while normal ejection of the product is not influenced, and further the production efficiency of the product is improved.

In the ejection mechanism of the die, the movable die is internally provided with the caulking groove penetrating through the top of the movable die, the ejector block is positioned in the caulking groove, the outer side of the head is provided with the guide surface, and when the top plate is reset and moves downwards, the guide surface can move along the edge of the notch of the caulking groove and compress the ejection spring.

When a section of the product is ejected, the ejector block part extends out of the caulking groove, the head of the core rod is not limited by the groove wall of the caulking groove any more, and the ejector block part automatically extends out of the part with larger size of the through hole under the action of the ejection spring, so that the core rod and the product are automatically separated. When the top plate is reset and moves downwards, the guide surface on the outer side of the head of the core rod moves along the edge of the notch of the caulking groove to enable the core rod to gradually compress the jacking spring, so that the rod part of the core rod can extend into the notch of the jacking block from the through hole, and the die can directly produce a product with a hole on the back-off part by using the core rod, thereby improving the production efficiency of the product.

In the ejection mechanism of the die, the side part of the ejector block is provided with the mounting groove communicated with the part with the larger size of the through hole, the outer side of the head part of the core rod is provided with the abutting step, and the mounting groove is internally fixed with the limiting baffle which is partially positioned in the part with the larger size of the through hole and can abut against the abutting step.

Through the arrangement, the distance that the core rod moves under the action of the elastic force of the jacking spring can be limited, the phenomenon that the core rod stretches out excessively and cannot be reset by the aid of the first guide surface or the second guide surface when the top plate is reset and moves downwards is avoided, and the reliability of a product with holes on the inverted buckle part is ensured by the aid of the core rod.

In the ejection mechanism of the die, the positioning seat with the mounting cavity is fixed on the top plate, the lower end of the ejector rod II is positioned in the mounting cavity, the linkage structure comprises a supporting spring positioned in the mounting cavity, an annular shoulder arranged outside the lower end of the ejector rod II and an annular shoulder protruding out of the inner side wall of the mounting cavity, the ejector rod II penetrates through the center of the annular shoulder, and two ends of the supporting spring respectively lean against the bottom wall of the mounting cavity and the lower end of the ejector rod II and lean against the upper side wall of the annular shoulder and the lower side wall of the annular shoulder.

The elastic force of the supporting spring acts on the ejector rod II upwards, so that the upper side wall of the annular shoulder at the lower end of the ejector rod II is propped against the lower side wall of the annular shoulder protruding out of the inner wall of the mounting cavity, and the ejector rod II can synchronously move by means of the cooperation when the top plate just starts to move upwards, and the ejector rod I and the ejector rod II can be driven to synchronously move to finish one-section ejection of a product when the top plate initially moves; when the abutting part abuts against the movable die, the upward movement of the second ejector rod is blocked, and the top plate can continue to move upward relative to the second ejector rod through compression of the supporting spring, so that the second ejection of the product is completed through further movement of the first ejector rod, and the part of the product, which is reversely buckled at the notch of the ejector block, is separated from the ejector block.

Through the mutual matching of the supporting spring, the annular retaining shoulder and the annular shoulder, the top plate can stably drive the ejector rod II to move upwards in the initial stage, and the reliability of the product during ejection is ensured. The two sides of the push rod are driven to move upwards by the friction force generated by the plunger pushing, and the product cannot be ejected smoothly due to the fact that the direction of the plunger force is perpendicular to the moving direction of the push rod.

In the ejection mechanism of the die, the positioning seat comprises a lower seat body fixedly connected to the top plate through a fastener and an upper seat body screwed on the lower seat body, the mounting cavity is formed by connecting the lower seat body with the upper seat body, and the annular shoulder is located on the upper seat body.

Specifically, when assembling, place supporting spring on lower pedestal, then pass last pedestal thread connection on lower pedestal from bottom to top with ejector pin two, form the installation cavity by last pedestal and lower pedestal and make supporting spring's elasticity can upwards act on ejector pin two, finally fix the positioning seat on the roof with the fastener again. Therefore, the second ejector rod, the supporting spring and the positioning seat form an independent assembly, and later maintenance is facilitated.

In the ejection mechanism of the die, the ejector rod II comprises a main rod body and an auxiliary rod body, the lower end of the auxiliary rod body is located in the positioning seat, the upper end of the auxiliary rod body is provided with a connecting hole, the lower end of the main rod body is inserted in the connecting hole, the main rod body and the auxiliary rod body are fixed through connecting screws, the rod parts of the connecting screws penetrate through the auxiliary rod body from bottom to top and are in threaded connection with the lower end of the main rod body, the lower seat body is fixed at the bottom of the top plate, and an operation hole communicated with the installation cavity is formed in the bottom of the lower seat body.

The second ejector rod is arranged to comprise a main rod body and an auxiliary rod body, and the main rod body and the auxiliary rod body penetrate through the auxiliary rod body from bottom to top through the rod part and are connected with a connecting screw in the lower end of the main rod body in a threaded manner. Simultaneously, fix the operation hole that is linked together with the installation cavity in the bottom of roof and setting up in the bottom of lower pedestal with lower pedestal, the staff can directly insert the installation intracavity with the screwdriver in the operation hole like this and demolish connecting screw to make the staff demolish except that the external whole ejection mechanism of mobile jib under the condition that does not involve the kicking block, further improved the convenience of later maintenance.

Compared with the prior art, the ejection mechanism of the die has the advantages that through the through hole is formed in the ejector block, the core rod is arranged in the through hole, one end of the core rod is abutted against the side wall of the movable die at the embedded position of the ejector block, the other end of the core rod extends out of the through hole and is positioned at the notch of the ejector block, and when melt plastics are injected into the die, the part of a molded product, which is reversely buckled at the notch, can be directly provided with a hole by means of the existence of the end of the core rod extending out of the notch of the ejector block, so that the production efficiency is improved. Meanwhile, a jacking spring acting on the core rod in the direction away from the notch is arranged in the through hole, and one side wall of the movable mould where the jacking block is embedded is obliquely arranged, so that the core rod can continuously move in the direction away from the notch by utilizing the elasticity of the jacking spring along with the formation of an increasingly larger gap between the jacking block and the side wall of the movable mould in the process of one-time ejection of a product, and the core rod is automatically separated from the product, so that the normal ejection action of the product is not influenced by the arrangement of the core rod.

Drawings

Fig. 1 is a cross-sectional view of an ejection mechanism of the present mold.

Fig. 2 is an enlarged sectional view of a linkage structure between the lower ends of the ejector pins and the top plate in fig. 1.

Fig. 3 is an enlarged cross-sectional view of the top block of fig. 2.

Fig. 4 is a side view of the side of the top block where the larger portion of the through hole is located.

Fig. 5 is a schematic cross-sectional view in the direction A-A of fig. 4.

Fig. 6 is a cross-sectional view of the ejection mechanism of the present mold after a section of ejection is completed.

Fig. 7 is an enlarged cross-sectional view of the top block of fig. 6.

Fig. 8 is a cross-sectional view of the ejection mechanism of the present mold after two-stage ejection is completed.

In the figure, 1, a movable mould; 1a, caulking groove; 2. a top block; 2a, a notch; 2b, through holes 2c, mounting grooves; 3. a top plate; 3a, a first abdicating hole; 4. a first ejector rod; 5. a second ejector rod; 5a, an abutting part; 5b, an annular shoulder; 5c, a main rod body; 5d, an auxiliary rod body; 6. a positioning seat; 6a, a mounting cavity; 6b, an annular shoulder; 6c, a lower seat body; 6c1, an operation hole; 6d, an upper seat body; 7. a support spring; 8. a core bar; 8a, a head; 8a1, a guide surface; 8a2, abutting the step; 8b, a rod part; 9. a pressing spring; 10. a limiting baffle; 11. a base; 11a, connecting columns; 11b, seat plate; 11b1, relief holes two; 12. and (5) connecting screws.

Detailed Description

The following are specific embodiments of the present invention and the technical solutions of the present invention will be further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1, 2 and 3, the ejection mechanism of the mold comprises a top plate 3 located below the movable mold 1 and capable of moving upwards, and a first ejector rod 4 and a second ejector rod 5 (in practice, the number of the first ejector rods 4 is a plurality of the first ejector rods, only one is shown in the embodiment), a base 11 is fixed below the movable mold 1, the top plate 3 is located inside the base 11, a hydraulic cylinder (not shown in the drawings) is connected to the bottom of the base 11, and the top plate 3 is fixedly connected with the upper end part of a piston rod of the hydraulic cylinder, so that the top plate 3 can be driven to move upwards when the piston rod of the hydraulic cylinder ejects upwards or the top plate 3 can be pulled to move downwards when the piston rod of the hydraulic cylinder retracts downwards to reset. The movable die 1 is provided with a first positioning hole penetrating through two ends and a second positioning hole penetrating through two ends, an upper end hole of the first positioning hole penetrates through the top of the movable die 1, a first ejector rod 4 penetrates through the first positioning hole and is fixed with a top plate 3 at the lower end of the first ejector rod, an upper end hole opening of the second positioning hole is communicated with the movable die 1 embedded by the ejector block 2, a second ejector rod 5 penetrates through the second positioning hole and is fixed with the ejector block 2 embedded in the top of the movable die 1 and provided with a notch 2a at one side, in practice, a caulking groove 1a penetrating through the top of the movable die 1 is arranged in the movable die 1, the ejector block 2 is positioned in the caulking groove 1a, and an upper end hole opening of the second positioning hole is communicated with the caulking groove 1 a. A linkage structure capable of enabling the two to move upwards synchronously is arranged between the lower end of the ejector rod II 5 and the top plate 3, and an abutting part 5a capable of abutting against the movable mould 1 to enable the top plate 3 to be in linkage with the ejector rod II 5 is arranged on the outer side of the ejector rod II 5.

In this embodiment, as shown in fig. 1 and 2, a positioning seat 6 with a mounting cavity 6a is fixed on the top plate 3, the lower end of the second ejector rod 5 is located in the mounting cavity 6a, the linkage structure comprises a supporting spring 7 located in the mounting cavity 6a, an annular shoulder 5b arranged outside the lower end of the second ejector rod 5 and an annular shoulder 6b protruding out of the inner wall of the mounting cavity 6a, the second ejector rod 5 passes through the center of the annular shoulder 6b, and two ends of the supporting spring 7 respectively abut against the bottom wall of the mounting cavity 6a and the lower end of the second ejector rod 5 and make the upper side wall of the annular shoulder 5b abut against the lower side wall of the annular shoulder 6 b. The elastic force of the supporting spring 7 acts on the ejector rod II 5 upwards, so that the upper side wall of the annular shoulder 5b at the lower end of the ejector rod II 5 is propped against the lower side wall of the annular shoulder 6b protruding out of the inner wall of the mounting cavity 6a, and thus the ejector rod II 5 can synchronously move, namely form linkage, by means of the cooperation when the top plate 3 just starts to move upwards, the ejector rod I4 and the ejector rod II 5 can be driven to synchronously move when the top plate 3 initially moves to finish one-section ejection of a product, and the state after one-section ejection is finished is shown in fig. 6 and 7; when the abutting part 5a abuts against the movable die 1, the upward movement of the second ejector rod 5 is blocked, and the top plate 3 can continue to move upward relative to the second ejector rod 5 due to the compression of the supporting spring 7, namely, the linkage of the top plate 3 and the second ejector rod 5 is released, so that the second ejection of the product is completed through the further movement of the first ejector rod 4, the part of the product, which is reversely buckled at the notch 2a of the ejector block 2, is separated from the ejector block 2, and the state after the second ejection is completed is shown in fig. 8. The positioning seat 6 comprises a lower seat body 6c fixedly connected to the top plate 3 through a fastener and an upper seat body 6d in threaded connection with the lower seat body 6c, the installation cavity 6a is formed by connecting the lower seat body 6c with the upper seat body 6d, and the annular retaining shoulder 6b is positioned on the upper seat body 6d. The second ejector rod 5 comprises a main rod body 5c and an auxiliary rod body 5b, the lower end of the auxiliary rod body 5b is positioned in the positioning seat 6, the upper end of the auxiliary rod body 5b is provided with a connecting hole, the lower end of the main rod body 5c is inserted in the connecting hole, the main rod body 5c and the auxiliary rod body 5d are fixed through a connecting screw, the rod part of the connecting screw penetrates through the auxiliary rod body 5d from bottom to top and is in threaded connection with the lower end of the main rod body 5c, the abutting part 5a is the upper end part of the auxiliary rod body 5b, and the outer diameter of the second auxiliary rod body 5b is larger than the aperture of the second positioning hole. In this embodiment, the top plate 3 is provided with a yielding hole 3a, the lower seat 6c is fixedly connected to the bottom of the top plate 3, the upper seat 6d is located in the yielding hole 3a, and an operation hole 6c1 communicated with the installation cavity 6a is provided at the bottom of the lower seat 6 c. The base 11 comprises a connecting column 11a fixedly connected to the bottom of the movable die 1 and a seat board 11b fixedly connected with the connecting column 11a through a fastener, a second yielding hole 11b1 is formed in the seat board 11b, and the bottom of the lower base 6c is located in the second yielding hole 11b 1.

Further, as shown in fig. 1, 2, 4 and 5, the top block 2 is provided with a through hole 2b, a core rod 8 and a pressing spring 9 are disposed in the through hole 2b, one end of the core rod 8 extends out of the through hole 2b and is located in a notch 2a of the top block 2, the pressing spring 9 acts on the core rod 8 in a direction away from the notch 2a, a side wall of the movable mold 1 in the embedded position of the top block 2 is obliquely arranged, that is, a side wall of the caulking groove 1a is obliquely arranged, the other end of the core rod 8 abuts against the side wall, and a gap for the core rod 8 to move in a direction away from the notch 2a is formed between the side wall and the top block 2 in the process that the top plate 3 drives the two ejector rods 5 to move upwards synchronously. Specifically, the through hole 2b is a stepped hole, a smaller-sized portion of the through hole 2b is communicated with the notch 2a in the side portion of the top block 2, the core rod 8 has a head 8a located in a larger-sized portion of the through hole 2b and a rod 8b penetrating out of the smaller-sized portion of the through hole 2b, and the pressing spring 9 is fitted over the rod 8b located in the larger-sized portion of the through hole 2b with its both ends respectively abutted against the stepped surfaces in the head 8a and the through hole 2 b. The outer side of the head 8a is provided with a guide surface 8a1, and when the top plate 3 is reset and moves downwards, the guide surface 8a1 can move along the notch edge of the caulking groove 1a and compress the pressing spring 9. Further, a mounting groove 2c communicated with a larger-sized portion of the through hole 2b is formed in the side portion of the top block 2, an abutting step 8a2 is formed on the outer side of the head portion 8a of the core rod 8, a limiting baffle 10 which is partially located in the larger-sized portion of the through hole 2b is fixed in the mounting groove 2c through a fastener, and the abutting step 8a2 can abut against the limiting baffle 10 when the core rod 8 moves under the action of the pressing spring 9.

The ejection mechanism is characterized in that a through hole 2b is formed in the ejector block 2, a core rod 8 is arranged in the through hole 2b, the head 8a of the core rod 8 is abutted against one side wall of the movable die 1 where the ejector block 2 is embedded, and the rod 8b of the core rod 8 extends out of the through hole 2b and is positioned at the notch 2a of the ejector block 2, so that when melt plastics are injected into the die, the part of a molded product, which is reversely buckled at the notch 2a, can be directly provided with a hole by means of the existence of the part of the rod 8b of the core rod 8 extending out of the notch 2 a. In addition, a pressing spring 9 acting on the core rod 8 in a direction away from the notch 2a is further arranged in the through hole 2b, a side wall of the movable die 1 abutting against one end of the core rod 8 in the position embedded by the pressing spring 9 is obliquely arranged, and in the process of driving the second ejector rod 5 to move upwards by the top plate 3 until the abutting part 5a abuts against the movable die 1 (namely, in the first ejection process of the product), a gap for the core rod 8 to move in a direction away from the notch 2a is formed between the pressing block 2 and the side wall, and the gap is gradually increased along with the continuous upward movement of the second ejector rod 5, so that the core rod 8 can continuously move in a direction away from the notch 2a under the action of the pressing spring 9 while the pressing block 2 is moved upwards, and the part of the core rod 8 is automatically separated from the notch 2a of the product after the first ejection of the product is completed, that is separated from the product, and the part of the core rod 8 is separated from the product at the notch 2a of the second ejector rod can still be smoothly completed. Through the arrangement, the product with holes on the back-off part can be directly produced by the die while the product can be normally ejected, and the holes do not need to be additionally machined after the injection molding of the product, so that the production efficiency of the product is improved.

After the product is taken out, the hydraulic cylinder drives the top plate 3 to move downwards for resetting, the first ejector rod 4 and the second ejector rod 5 (specifically, the top plate 3 is pressed on the annular stop shoulder 6b through the annular shoulder 5b on the positioning seat 6 to form a lower thrust for the second ejector rod 5) also move downwards along with the top plate 3 for resetting, the ejector block 2 is embedded into the caulking groove 1a at the top of the movable die 1 again, in the process, the core rod 8 moves along the notch edge of the caulking groove 1a through the guide surface 8a1 at the head 8a to gradually compress the ejector spring 9, so that the rod part 8b of the core rod 8 can extend out to the notch 2a of the ejector block 2 again to ensure that a required hole can be directly formed on the part of the ejector block 2 when the product is reversely buckled in the next injection molding.

The specific embodiments described herein are offered by way of example only to illustrate the spirit of the invention. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions thereof without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Claims

1. The ejection mechanism of the die comprises a top plate (3) positioned below the movable die (1) and a first ejector rod (4) and a second ejector rod (5) which are respectively penetrated in the movable die (1), wherein the lower end of the first ejector rod (4) is fixed with the top plate (3), the upper end of the second ejector rod (5) is fixed with an ejector block (2) embedded in the top of the movable die (1) and provided with a notch (2 a) on one side, a linkage structure which can enable the top plate (3) to drive the second ejector rod (5) to synchronously move upwards is arranged between the lower end of the ejector block and the top plate (3), the outer side of the second ejector rod (5) is provided with an abutting part (5 a) which can abut against the movable die (1) to enable the top plate (3) and the second ejector rod (5) to be in a releasing linkage mode, the ejection mechanism is characterized in that a through hole (2 b) is arranged on the ejector block (2), a core rod (8) and an ejector spring (9) are arranged in the through hole (2 b), one end of the core rod (8) extends out of the through hole (2 b) and is positioned at the notch (2 a) of the ejector block (2) and the ejector spring (9) is arranged on one side of the opposite side of the ejector rod (8) and far away from the notch (8) in the direction of the side of the movable die (2), in the process that the top plate (3) drives the ejector rod II (5) to move upwards, a gap for the core rod (8) to move towards the direction far away from the notch (2 a) is formed between the ejector block (2) and the side wall.

2. The ejection mechanism of the mold according to claim 1, wherein the through hole (2 b) is a stepped hole, the core bar (8) has a head portion (8 a) located in a larger portion of the through hole (2 b) and a stem portion (8 b) penetrating out of a smaller portion of the through hole (2 b), and the ejector spring (9) is sleeved out of the stem portion (8 b) located in the larger portion of the through hole (2 b) and both ends thereof respectively abut against stepped surfaces in the head portion (8 a) and the through hole (2 b).

3. The ejection mechanism of a mold according to claim 2, wherein the movable mold (1) is provided with a caulking groove (1 a) penetrating through the top of the movable mold, the ejector block (2) is positioned in the caulking groove (1 a), the outer side of the head part (8 a) is provided with a guide surface (8 a 1), and when the top plate (3) is reset to move downwards, the guide surface (8 a 1) can move along the edge of a notch of the caulking groove (1 a) and compress the ejection spring (9).

4. A mould ejection mechanism according to claim 3, wherein the side of the ejector block (2) is provided with a mounting groove (2 c) communicated with a larger part of the through hole (2 b), the outer side of the head (8 a) of the core rod (8) is provided with an abutting step (8 a 2), and a limiting baffle (10) which is partially positioned in the larger part of the through hole (2 b) and can abut against the abutting step (8 a 2) is fixed in the mounting groove (2 c).

5. The ejection mechanism of a mold according to claim 1, 2, 3 or 4, wherein a positioning seat (6) with a mounting cavity (6 a) is fixed on the top plate (3), the lower end of the second ejector rod (5) is located in the mounting cavity (6 a), the linkage structure comprises a supporting spring (7) located in the mounting cavity (6 a), an annular shoulder (5 b) arranged outside the lower end of the second ejector rod (5) and an annular shoulder (6 b) protruding out of the inner side wall of the mounting cavity (6 a), the second ejector rod (5) penetrates through the center of the annular shoulder (6 b), and two ends of the supporting spring (7) respectively lean against the bottom wall of the mounting cavity (6 a) and the lower end of the second ejector rod (5) and lean against the upper side wall of the annular shoulder (5 b) and the lower side wall of the annular shoulder (6 b).

6. The ejection mechanism of a mold according to claim 5, wherein the positioning seat (6) comprises a lower seat body (6 c) fixedly connected to the top plate (3) through a fastener and an upper seat body (6 d) screwed on the lower seat body (6 c), the installation cavity (6 a) is formed by connecting the lower seat body (6 c) with the upper seat body (6 d), and the annular shoulder (6 b) is located on the upper seat body (6 d).

7. The ejection mechanism of a mold according to claim 6, wherein the ejector rod II (5) comprises a main rod body (5 c) and an auxiliary rod body (5 d), the lower end of the auxiliary rod body (5 d) is located in the positioning seat (6), the upper end of the auxiliary rod body (5 d) is provided with a connecting hole, the lower end of the main rod body (5 c) is inserted into the connecting hole, the main rod body (5 c) and the auxiliary rod body (5 d) penetrate through the auxiliary rod body (5 d) from bottom to top through a rod part (8 b) and are in threaded connection with a connecting screw (12) in the lower end of the main rod body (5 c), the lower seat body (6 c) is fixed at the bottom of the top plate (3), and an operating hole (6 c 1) communicated with the installation cavity (6 a) is formed in the bottom of the lower seat body (6 c).