Sand core ejection mechanism and sand core mold

Abstract

The utility model relates to the technical field of casting molding, and particularly provides a sand core ejection mechanism and a sand core mold. The sand core ejection mechanism comprises an ejection mechanism arranged on a fixed mold of a sand core mold, the fixed mold comprises a fixed mold base and a fixed mold module arranged on the side, facing the movable mold, of the fixed mold base; the ejection mechanism comprises a fixed mold ejection rod arranged on the fixed mold module in a penetrating manner, and an elastic piece acting between the fixed mold seat and the fixed mold ejection rod; the end, close to the movable mold, of the fixed mold ejector rod extends to be flush with the inner wall of the fixed mold cavity. The elastic piece exerts elastic force on the fixed mold ejector rod in the mold opening direction, and along with mold opening of the movable mold, the fixed mold ejector rod can enter the fixed mold cavity under the action of the elastic force to eject the sand core located in the fixed mold cavity. According to the sand core ejection mechanism disclosed by the utility model, the fixed mold ejection rod can synchronously move under the action of elastic force during mold opening, and the sand core is ejected out of the fixed mold cavity, so that the sand core can be smoothly demolded during mold opening of a sand core mold.

Description

Technical Field

[0001] The utility model relates to the technical field of casting mold manufacturing, and particularly relates to a core ejection mechanism. In addition, the utility model also relates to a core mold. Background Art

[0002] In modern mechanical production and manufacturing processes, the casting process is an essential and important production process; for casting parts with internal cavities, it is necessary to pre-manufacture cores using core molds. For example, in the double-wishbone shock absorber suspension system of a vehicle, the shock absorber fork is a symmetrical part, and two cores with the same shape are required during its casting forming; the core is mostly filled with sand material into the core box by the vertical sand shooting process, and after the core is formed, the mold is opened, and the core is taken out and placed on the production line for subsequent processes. The sand shooting mold manufacturing process for such small cores has a fast production rhythm and low energy consumption, so it has a relatively wide application.

[0003] The general structure and setting of such core mold equipment are as shown in Figure 6 the attached drawings of the specification. The fixed mold is arranged on the left side of the operator, and the movable mold is arranged on the right side of the operator. During the specific production process, when the mold is opened, the movable mold retreats and moves away from the fixed mold, and the fixed mold uses an oil cylinder to drive the fixed mold ejector rod to eject the core. After the core is separated from the movable mold, the movable mold returns to its original position and closes with the fixed mold, and the reset rod will drive the ejector rod to reset; during the reset process, the reset spring changes from the compressed state to the extended state, playing a role in assisting the reset.

[0004] However, in actual processes, the oil cylinder for driving the ejector rod in the fixed mold and the oil cylinder for driving the movable mold to move away need to act synchronously in order to keep the core on the movable mold side when the mold is opened; but because it is difficult to achieve the synchronization of ejection and mold opening through mechanical structures, problems of non-synchronization between ejection and mold opening often occur. Ejection earlier than mold opening will cause the core to be crushed; ejection later than mold opening easily leads to the core being separated from the movable mold when the mold is opened, and the core is then ejected out of the fixed mold cavity and directly falls and is damaged. Due to the existence of the above problems, it will seriously affect the automatic production rhythm, thereby reducing the production efficiency. In addition, since it is necessary to set driving structures such as an oil cylinder for driving the ejector rod on the fixed mold, this will inevitably cause an increase in the size of the fixed mold side, which is not conducive to the overall spatial layout of the equipment. Summary of the Utility Model

[0005] In view of this, the utility model aims to propose a core ejection mechanism to facilitate the smooth demolding of the core.

[0006] To achieve the above object, the technical solution of the utility model is realized as follows:

[0007] A core ejection mechanism, including an ejection mechanism provided on the fixed mold of the core mold. The fixed mold includes a fixed mold base and a fixed mold module provided on one side of the fixed mold base facing the movable mold. The fixed mold cavity on the fixed mold module and the movable mold cavity on the movable mold module of the movable mold form a core box for molding the core.

[0008] The ejection mechanism includes a fixed mold ejector rod passing through the fixed mold module and an elastic member acting between the fixed mold base and the fixed mold ejector rod. The fixed mold ejector rod is arranged along the mold opening direction of the movable mold, and one end of the fixed mold ejector rod close to the movable mold extends to be flush with the inner wall of the fixed mold cavity. The elastic member applies an elastic force to the fixed mold ejector rod in the mold opening direction. As the movable mold opens, the fixed mold ejector rod can enter the fixed mold cavity under the action of the elastic force to eject the core located in the fixed mold cavity.

[0009] Furthermore, corresponding to each fixed mold cavity, a plurality of the fixed mold ejector rods are arranged at intervals on the fixed mold module.

[0010] Furthermore, the ejection mechanism further includes an ejector rod base and an ejector rod frame provided on the fixed mold base. The ejector rod base is fixedly installed on the fixed mold base, and the ejector rod frame can move relative to the fixed mold base in the mold opening direction. One end of the fixed mold ejector rod far from the movable mold is fixedly connected to the ejector rod frame, and the elastic member acts between the ejector rod base and the ejector rod frame.

[0011] Furthermore, a first positioning post is fixedly provided on one side of the ejector rod base facing the movable mold. The first positioning post is arranged along the mold opening direction. The elastic member includes a top pressure spring sleeved on the first positioning post, and a spring cap is sleeved outside the top pressure spring. The spring cap is connected to the ejector rod frame, and the top pressure spring transmits the elastic force to the fixed mold ejector rod through the spring cap and the ejector rod frame.

[0012] Furthermore, the ejector rod frame includes an ejector rod bottom plate and an ejector rod pressing plate stacked together. The end of the fixed mold ejector rod for connecting the ejector rod frame is formed with a radially protruding head. A groove for accommodating the head is provided on the ejector rod bottom plate, and the ejector rod pressing plate presses the head in the groove so that the fixed mold ejector rod is fixedly connected to the ejector rod frame.

[0013] Compared with the prior art, the present utility model has the following advantages:

[0014] The core ejection mechanism of the present utility model is such that when the fixed mold and the moving mold are in the closed mold state, the core is defined and formed in the core box formed between the fixed mold module and the moving mold module. By providing an ejection mechanism on the fixed mold base, an elastic member can apply an elastic force in the mold opening direction to the fixed mold ejector rod. When the end of the fixed mold ejector rod is flush with the inner wall of the fixed mold cavity in the closed mold state of the fixed mold and the moving mold, the core will not be pressed. When the mold is opened and the moving mold leaves the fixed mold, the fixed mold ejector rod can move synchronously under the elastic force to eject the core out of the fixed mold cavity, thus ensuring the synchronism of the mold opening and the ejection action of the fixed mold ejector rod, avoiding the situation that the ejection action of the fixed mold ejector rod is too early and damages the core, or the ejection action is too late and the core fails to leave with the moving mold, which is beneficial to the smooth demolding of the core when the core mold is opened.

[0015] In addition, by fixedly installing an ejector rod base on the fixed mold base and providing a movably guided ejector rod frame on the fixed mold base, it is convenient to fixedly install multiple fixed mold ejector rods on the ejector rod frame at the same time, and an elastic member is flexibly arranged between the ejector rod base and the ejector rod frame. In this way, it is beneficial to the reasonable arrangement of the fixed mold ejector rod and the elastic member, and it is also convenient to realize the balanced transmission of the driving force between the two. A first positioning column is provided on the ejector rod base, and a top compression spring is sleeved on the first positioning column and used as an elastic member, which can well guide the elastic force application direction of the top compression spring. Using a spring cap, the elasticity of the compressed top compression spring can be transmitted to the ejector rod frame, and then a thrust in the mold opening direction is transmitted to each fixed mold ejector rod.

[0016] Another object of the present utility model is to provide a core mold, and the fixed mold of the core mold is provided with the core ejection mechanism of the present utility model.

[0017] Furthermore, the moving mold includes a moving mold base, a substrate for carrying the moving mold base to move in the mold opening direction, and a driving device for driving the moving mold base to open the mold. The moving mold module is arranged on one side of the moving mold base facing the fixed mold, and a moving mold ejector rod penetrates through the moving mold module. The moving mold ejector rod is arranged along the mold opening direction, and the end of the moving mold ejector rod close to the fixed mold extends to be flush with the inner wall of the moving mold cavity. The mold opening movement path of the moving mold base includes a main movement section and an end section connected in front and back. When the moving mold base moves to the end section, the substrate can act on the moving mold ejector rod to drive the moving mold ejector rod into the moving mold cavity to eject the core located in the moving mold cavity.

[0018] Furthermore, a moving mold ejector rod seat is provided on the moving mold base, and the moving mold ejector rod seat can move relative to the moving mold base in the mold opening direction. The end of the moving mold ejector rod far from the fixed mold is fixedly connected to the moving mold ejector rod seat. A top column extending towards the fixed mold direction is provided on the substrate. When the moving mold base moves to the end section, the top column presses on the moving mold ejector rod seat to drive the moving mold ejector rod into the moving mold cavity.

[0019] Furthermore, a movable mold reset mechanism is provided between the movable mold module and the movable mold ejector seat, and the movable mold reset mechanism includes a movable mold reset spring that can elastically act between the movable mold module and the movable mold ejector seat; when the movable mold seat returns from the end section to the main moving section, the movable mold ejector can be retracted to a state where the end is flush with the inner wall of the movable mold cavity under the action of the movable mold reset spring.

[0020] Furthermore, a fixed mold reset rod is also provided on the fixed mold module, and the fixed mold reset rod is arranged along the mold opening direction, and one end of the fixed mold reset rod close to the movable mold extends to the end surface of the fixed mold module, and the other end of the fixed mold reset rod is transmission-connected with the fixed mold ejector rod. When the movable mold is closed onto the fixed mold, the movable mold module can press the fixed mold reset rod, thereby driving the fixed mold ejector rod to retract to a state where the end portion is flush with the inner wall of the fixed mold cavity; and / or, a movable mold reset rod is also provided on the movable mold module, and the movable mold reset rod is arranged along the mold opening direction, and one end of the movable mold reset rod close to the fixed mold extends to the end surface of the movable mold module, and the other end of the movable mold reset rod is transmission-connected with the movable mold ejector rod. When the movable mold is closed onto the fixed mold, the fixed mold module can press the movable mold reset rod, thereby driving the movable mold ejector rod to retract to a state where the end portion is flush with the inner wall of the movable mold cavity.

[0021] Compared with the existing sand core mold, the sand core ejection mechanism of the utility model is the opposite, changing the role of the fixed mold reset spring on the existing fixed mold. The fixed mold is no longer provided with a driving mechanism for actively ejecting the sand core, but the elastic member in the ejection mechanism is used to realize the passive ejection of the sand core, so that the top pressure spring is compressed when the movable mold is reset and closed, and the top pressure spring is stretched when the movable mold is opened to drive the fixed mold ejector to eject, and the elastic potential energy of the spring is used to do work to push the fixed mold ejector to push out the sand core, ensuring the synchronization of mold opening and sand core separation from the fixed mold. The sand core mold using the ejection mechanism of the utility model can basically ensure that the sand core is separated from the fixed mold and remains on the movable mold when the mold is opened without auxiliary demolding, and then falls off from the movable mold to the production line after the movable mold moves above the production line, ensuring the continuity of automated production and reducing the workload of manual removal of auxiliary demolding.

[0022] In addition, by arranging ejector pins on the moving die module, it is convenient to eject the core from the moving die cavity after the moving die opens and moves into place, so as to accurately drop onto the production line for subsequent processes. The driving device is used to drive the moving die base to move and open the die in the opening direction, and the opening movement path of the moving die base is divided into two parts: the main moving section and the end section; by designing a reasonable transmission structure between the substrate and the ejector pins according to the length dimensions of the main moving section and the end section, the ejector pins can be blocked at the end section to realize the pushing movement of the ejector pins relative to the moving die base, so that the core can be smoothly ejected from the moving die cavity by the ejector pins at the end section. The above setting method does not require a separate driving mechanism for driving the ejector pins on the moving die, thus reducing the number of driving components. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof are used to explain the present invention. The front-back, up-down and other orientation terms involved only represent relative positional relationships and do not constitute improper limitations on the present invention. In the drawings:

[0024] Figure 1 is a schematic overall sectional structure diagram of the core mold according to the embodiment of the present invention in the closed mold state;

[0025] Figure 2 is a schematic sectional structure diagram of the core mold according to the embodiment of the present invention when the core is ejected from the fixed die cavity at the beginning of mold opening;

[0026] Figure 3 is a schematic sectional structure diagram of the core mold according to the embodiment of the present invention after the moving die moves away from the fixed die;

[0027] Figure 4 is a schematic sectional structure diagram of the ejection mechanism according to the embodiment of the present invention in the closed mold state;

[0028] Figure 5 is a schematic sectional structure diagram of the ejection mechanism according to the embodiment of the present invention when the fixed die ejector pin ejects the core;

[0029] Figure 6 is a schematic overall sectional structure diagram of a core mold in the prior art;

[0030] Figure 7 is a schematic sectional structure diagram of the core mold according to the embodiment of the present invention when the moving die flips to make the core fall.

[0031] Description of the reference numerals:

[0032] 1. Fixed mold base; 10. Fixed mold die carrier plate; 100. Avoidance groove; 11. Fixed mold middle carrier plate; 12. Fixed mold rear carrier plate; 13. Fixed mold ejection oil cylinder; 130. First connecting frame; 14. Fixed mold ejector rod seat; 140. Fixed mold ejector rod fixing plate; 15. Fixed mold return spring;

[0033] 2. Fixed mold module; 20. Fixed mold cavity; 21. Fixed mold ejector rod; 22. Fixed mold return rod;

[0034] 3. Moving mold module; 30. Moving mold cavity; 31. Moving mold ejector rod; 32. Moving mold return rod;

[0035] 4. Moving mold base; 40. Moving mold die carrier plate; 41. Moving mold middle carrier plate; 410. Through hole; 411. Guide rod; 42. Moving mold rear carrier plate;

[0036] 5. Moving mold ejection oil cylinder; 50. Second connecting frame; 510. Fixed bottom plate; 511. Moving mold ejector rod fixing plate; 512. Moving mold ejector rod pressure plate; 520. Second positioning column; 521. Moving mold return spring; 53. Substrate; 54. Ejector pin; 55. Flip drive mechanism;

[0037] 6. Moving mold shifting oil cylinder; 60. Moving mold drive frame; 61. Moving mold drive oil cylinder; 610. Oil cylinder rod;

[0038] 7. Sand injection sand box; 70. Sand injection plate; 71. Sand injection hole;

[0039] 8. Sand core;

[0040] 9. Ejection mechanism; 90. Ejector rod base; 91. First positioning column; 910. Retaining ring; 920. Ejector rod bottom plate; 921. Ejector rod pressing plate; 922. Spring cap; 93. Top compression spring. Detailed implementation manners

[0041] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0042] In the description of the present invention, it should be stated that if terms indicating orientation or positional relationship such as "upper, lower, left, right, front, rear, inner, outer" appear, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed or operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0043] In addition, in the description of the present utility model, unless otherwise clearly defined, the terms "installation", "connection", "connection", and "connector" should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or even a communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood in combination with specific situations. In the description of the present utility model, the limiting terms such as "first, second, A, B, C, D" are only used to distinguish the same type of features in different positions, ownerships, or uses, etc., in order to achieve the purpose of avoiding ambiguity and confusion in the description, and cannot be understood as indicating or implying relative importance.

[0044] In addition, in the embodiments of the present utility model, ejector pins such as the fixed mold ejector pin and the moving mold ejector pin are flush with the inner wall of the core box in the mold-closed state so as to form a sand core in the core box; during demolding, they extend into the core box to push the sand core out of the fixed mold cavity or the moving mold cavity. The reset rods such as the fixed mold reset rod and the moving mold reset rod are slightly longer than the ejector pins. When the mold is opened, they extend outside the parting end face of the fixed mold module or the moving mold module. When the mold is closed, they are pressed by the moving mold module or the fixed mold module and retract to a position flush with the parting end face of the fixed mold module and the moving mold module, and drive the fixed mold ejector pin and the moving mold ejector pin to retract to the reset position and maintain a state flush with the inner wall of the core box at their ends.

[0045] The present utility model will be described in detail below with reference to the drawings and in combination with embodiments.

[0046] Embodiment 1

[0047] This embodiment relates to a sand core ejection mechanism provided on the fixed mold of a sand core mold, which is conducive to the smooth demolding of the sand core 8; an exemplary structure thereof is as Figure 1 , Figure 2 and Figure 3 shown.

[0048] Generally speaking, the above-mentioned fixed mold includes a fixed mold base 1 and a fixed mold module 2 provided on the side of the fixed mold base 1 facing the moving mold. The fixed mold cavity 20 on the fixed mold module 2 and the moving mold cavity 30 on the moving mold module 3 of the moving mold form a core box for forming a sand core 8. The ejection mechanism 9 includes a fixed mold ejector pin 21 penetrating through the fixed mold module 2 and an elastic member acting between the fixed mold base 1 and the fixed mold ejector pin 21. Among them, the fixed mold ejector pin 21 is arranged along the mold-opening direction of the moving mold, and the end of the fixed mold ejector pin 21 close to the moving mold extends to be flush with the inner wall of the fixed mold cavity 20; the elastic member applies an elastic force to the fixed mold ejector pin 21 in the mold-opening direction. As the moving mold opens, the fixed mold ejector pin 21 can enter the fixed mold cavity 20 under the action of the elastic force to eject the sand core 8 located in the fixed mold cavity 20.

[0049] It should be noted that based on the above overall design concept, the technical solution of the present utility model can adopt a variety of different specific implementation structures, forms or configuration sequences. For example, the above elastic member can adopt components with different specific structural forms such as springs and elastic pads; the specific connection form and installation method between the elastic member and the fixed mold ejector rod 21 can also be flexibly adjusted. For parts required for the implementation of the overall solution but not involved in the above overall settings, reasonable and flexible designs can be made with reference to mature setting means in the art, actual situations during implementation, etc. The following specific implementation solutions in this embodiment are only one of the relatively optimal solutions among the many solutions that can be formed by the above various combinations and their variations. In actual implementation, those skilled in the art can make flexible adjustments and improvements in combination with actual situations. Obviously, the many solutions that can be formed by the above various specific form combinations and their variations, as well as the specific implementation solutions of this embodiment, are all within the protection scope of the present utility model.

[0050] As Figure 1 , Figure 2 shown, the core sand mold shown in this embodiment belongs to a horizontal core making machine, and a sand injection sand box 7 must be provided above it. That is, the core box in this embodiment is a vertical sand injection core box, and the parting surface of the fixed mold module 2 and the moving mold module 3 is perpendicular to the ground; however, the ejecting mechanism 9 of the present utility model can also be applied to other forms of core sand molds.

[0051] Of course, one or more core boxes can be provided in the same core sand mold; for example, when prefabricating the core sand 8 of a vehicle shock absorber fork, since the shock absorber fork is a symmetric part with two identical inner cavities, two identical core sands 8 are required for the same shock absorber fork; the core sand mold of the present utility model takes the core sand 8 of the prefabricated shock absorber fork as an example for illustration, and two core boxes are provided between the fixed mold module 2 and the moving mold module 3 of the core sand mold. In this embodiment, as Figure 1 , Figure 2 shown, for each core box, a fixed mold cavity 20 will be correspondingly provided on the fixed mold module 2, and one or more fixed mold ejector rods 21 can be provided corresponding to each fixed mold cavity 20; two fixed mold ejector rods 21 are provided in the fixed mold cavity 20 of this embodiment. By providing multiple fixed mold ejector rods 21 for the fixed mold cavity 20, the force balance during the ejection of the core sand 8 can be ensured, so that the core sand 8 can be more smoothly separated from the fixed mold cavity 20.

[0052] As Figure 3 and in combination with Figure 4 , Figure 5As shown in the figure, the ejection mechanism 9 of this embodiment further includes an ejector rod base 90 and an ejector rod frame provided on the fixed mold base 1. The ejector rod base 90 is fixedly installed on the fixed mold base 1, and the ejector rod frame can move relative to the fixed mold base 1 in the mold opening direction. At the same time, the end of the fixed mold ejector rod 21 away from the moving mold is fixedly connected to the ejector rod frame, and the elastic member acts between the ejector rod base 90 and the ejector rod frame. By fixedly installing the ejector rod base 90 on the fixed mold base 1 and arranging a guideable moving ejector rod frame on the fixed mold base 1, it is convenient to fixedly install multiple fixed mold ejector rods 21 on the ejector rod frame at the same time and flexibly arrange the elastic member between the ejector rod base 90 and the ejector rod frame; this is beneficial to the reasonable arrangement of the fixed mold ejector rod 21 and the elastic member and also facilitates the balanced transmission of the driving force between the two.

[0053] As previously mentioned, there are various forms of setting the elastic member. In this embodiment, a first positioning column 91 is fixedly provided on the side of the ejector rod base 90 facing the moving mold, and the first positioning column 91 is arranged along the mold opening direction; the elastic member includes a top compression spring 93 sleeved on the first positioning column 91, and a spring cap 922 is sleeved outside the top compression spring 93; the spring cap 922 is connected to the ejector rod frame, and the top compression spring 93 transmits the elastic force to the fixed mold ejector rod 21 through the spring cap 922 and the ejector rod frame. By setting the first positioning column 91 on the ejector rod base 90 and sleeving the top compression spring 93 on the first positioning column 91 for use as the elastic member, the elastic force application direction of the top compression spring 93 can be well guided. Using the spring cap 922, the elasticity of the compressed top compression spring 93 can be transmitted to the ejector rod frame, and then a thrust in the mold opening direction is transmitted to each fixed mold ejector rod 21.

[0054] Moreover, the spring cap 922 of this embodiment is a cylindrical barrel-shaped structure with a flange-type flanging at the end. Its flanging can be pressed by the ejector rod pressing plate 921 on the ejector rod bottom plate 920, and its inner cavity forms a spring chamber for accommodating the top compression spring 93, providing a good enclosed space for the top compression spring 93 and being beneficial to improving the service durability of the top compression spring 93. In addition, to improve the top pressure application effect between the top compression spring 93 and the ejector rod base 90, the head of the first positioning column 91 of this embodiment can be welded to the ejector rod base 90, and a retaining ring 910 is sleeved on the column body of the first positioning column 91, so that the top compression spring 93 applies force to the ejector rod base 90 by pressing the retaining ring 910, so that both ends of the top compression spring 93 have stable force application points.

[0055] Based on the above settings, preferably, the ejector rod frame of this embodiment includes an ejector rod bottom plate 920 and an ejector rod pressing plate 921 stacked together. The end of the fixed mold ejector rod 21 for connecting the ejector rod frame is formed with a radially protruding head, and the ejector rod bottom plate 920 is provided with a groove for accommodating the head. The ejector rod pressing plate 921 presses the head in the groove so that the fixed mold ejector rod 21 is fixedly connected to the ejector rod frame.

[0056] The ejector rod holder is designed into two parts, namely an ejector rod bottom plate 920 and an ejector rod pressing plate 921 arranged in a stacked manner, which facilitates the arrangement and fixation of each fixed mold ejector rod 21 on the ejector rod holder. Based on the above settings, the end of the spring cap 922 facing away from the moving mold can also be pressed and fixed between the ejector rod pressing plate 921 and the ejector rod bottom plate 920 in a similar manner to the fixed mold ejector rod 21; meanwhile, in order to conveniently install the fixed mold module 2 on the fixed mold base 1, a fixed mold die carrier plate 10 is provided on one side of the fixed mold base 1 close to the moving mold, and an avoidance groove 100 is opened on the fixed mold die carrier plate 10 to provide sufficient space for the movement of the spring cap 922.

[0057] In summary, for the ejection mechanism 9 of this embodiment, when the fixed mold and the moving mold are in the closed mold state, the sand core 8 is defined and formed in the core box formed between the fixed mold module 2 and the moving mold module 3; by providing the ejection mechanism 9 on the fixed mold base 1, the elastic member can apply an elastic force in the mold opening direction to the fixed mold ejector rod 21. When the end of the fixed mold ejector rod 21 is flush with the inner wall of the fixed mold cavity 20 in the closed mold state of the fixed mold and the moving mold, the sand core 8 will not be pressed; when the mold is opened and the moving mold leaves the fixed mold, the fixed mold ejector rod 21 can move synchronously under the elastic force to eject the sand core 8 out of the fixed mold cavity 20, thus ensuring the synchronism of the mold opening and the ejection action of the fixed mold ejector rod 21, avoiding the situation that the ejection action of the fixed mold ejector rod 21 is too early and damages the sand core 8, or the ejection action is too late and the sand core 8 fails to leave with the moving mold, which is beneficial to the smooth demolding of the sand core 8 when the sand core mold is opened.

[0058] Embodiment 2

[0059] This embodiment relates to a sand core mold, and the fixed mold of the sand core mold is provided with the sand core ejection mechanism provided in Embodiment 1; an exemplary structure of the sand core mold is as Figure 1 、 Figure 2 and Figure 3 shown.

[0060] To better understand the differences between the sand core mold of the present invention and the existing sand core molds, the general structure of the existing sand core molds will be introduced below in combination with Figure 6 .

[0061] As Figure 6As shown in the figure, in the existing core sand mold, mold base plates 10, middle mold base plates 11 and rear mold base plates 12 are arranged at intervals on the fixed mold base 1 of the fixed mold. The fixed mold base plates 10 and the rear mold base plates 12 are respectively located on both sides of the middle mold base plates 11 of the fixed mold, and the fixed mold modules 2 are fixedly installed on the fixed mold base plates 10. A fixed mold ejector cylinder 13 is installed on the rear mold base plate 12 of the fixed mold. The fixed mold ejector cylinder 13 drives the fixed mold ejector rod seat 14 to move through the first connecting frame 130. The fixed mold ejector rod 21 is fixedly pressed on the fixed mold ejector rod seat 14 through the fixed mold ejector rod fixing plate 140. A fixed mold return spring 15 is arranged between the fixed mold ejector rod seat 14 and the fixed mold base plate 10. On the moving mold base 4 of the moving mold, moving mold base plates 40, middle moving mold base plates 41 and rear moving mold base plates 42 are arranged at intervals. The moving mold modules 3 are fixedly installed on the moving mold base plates 40. A moving mold ejector rod seat that can move in the mold opening direction is arranged between the middle moving mold base plates 41 and the moving mold base plates 40. The moving mold ejector rod 31 and the moving mold return rod 32 are both fixedly connected to the moving mold ejector rod seat. The moving mold ejector rod seat is driven by the moving mold ejector cylinder 5 through the second connecting frame 50 to drive the moving mold ejector rod 31 to perform the action of ejecting the core sand 8. At the same time, the moving mold base 4 is also provided with a moving mold displacement cylinder 6. The moving mold displacement cylinder 6 drives the moving mold base 4 to move in the mold opening direction through the moving mold driving frame 60 to perform the mold opening action.

[0062] During mold opening, while the moving mold displacement cylinder 6 drives the moving mold base 4 to start moving, the fixed mold ejector cylinder 13 needs to synchronously drive the first connecting frame 130 in the mold opening direction, and then drive the fixed mold ejector rod 21 to eject the core sand 8 through the fixed mold ejector rod seat 14 and the fixed mold ejector rod fixing plate 140, so that the core sand 8 moves with the moving mold; when the fixed mold ejector rod seat 14 and the fixed mold ejector rod fixing plate 140 move, the fixed mold return spring 15 located between the fixed mold ejector rod fixing plate 140 and the fixed mold base plate 10 will be compressed. After the moving mold retreats a certain distance, it turns downward to align with the assembly line. At this time, the moving mold ejector cylinder 5 on the moving mold base 4 drives the second connecting frame 50, and then drives the moving mold ejector rod 31 to eject the core sand 8 through the moving mold ejector rod seat. The core sand 8 will fall off the moving mold cavity 30 on the moving mold module 3 onto the assembly line; at the same time, the moving mold return spring 521 will be compressed. During mold closing, the moving mold ejector cylinder 5 of the moving mold and the fixed mold ejector cylinder 13 of the fixed mold first return to their original positions. The moving mold turns back to the horizontal posture and moves towards the fixed mold side. As the distance between the moving mold and the fixed mold gradually decreases until mold closing is completed, the fixed mold return rod 22 touches the moving mold module 3, driving the fixed mold ejector rod seat 14 and the fixed mold ejector rod 21 to return to their original positions; the moving mold return rod 32 touches the fixed mold module 2, driving the moving mold ejector rod seat and the moving mold ejector rod 31 to return to their original positions. During the reset process, the fixed mold return spring 15 and the moving mold return spring 521 change from the compressed state to the stretched state, playing an auxiliary reset role.

[0063] From the above understanding of the entire mold opening process of the existing core mold, it can be seen that the key lies in ensuring the synchronization of the driving actions of the fixed mold ejection cylinder 13 and the moving mold displacement cylinder 6. Otherwise, it is easy for the core 8 to be crushed by extrusion or for the core 8 to fail to separate from the fixed mold cavity 20 in time and follow the moving mold during movement. Moreover, the length of the moving mold opening movement path is usually 100 mm - 600 mm, while the ejection stroke of the fixed mold ejector rod 21 in the fixed mold is very short, usually only 5 mm - 10 mm. Since the mold opening and ejection of the equipment cannot use the same cylinder, the absolute synchronization of mold opening and ejection cannot be achieved, and it is relatively dependent on the parting experience design of the core box, with uncertainty.

[0064] At the same time, due to the diversity of products, it is very difficult to distinguish the demolding force of many cores 8 (such as symmetrical parts), and it is particularly easy for the core 8 to remain on the fixed mold during mold opening. To prevent the inability to take the core normally and affect the production progress, for cores 8 with symmetry or little difference between the left and right molds, relevant structures for assisting in pulling out the core 8 are generally made on the moving mold side during parting, which increases the workload of later removal or repair. Even so, it cannot be guaranteed 100% that the core 8 will remain on the moving mold, so the above problems still often occur.

[0065] Compared with the existing core mold, the ejection mechanism 9 of this embodiment acts in the opposite way and changes the function of the fixed mold return spring 15 on the existing fixed mold. No driving mechanism for actively ejecting the core 8 is provided on the fixed mold. Instead, the elastic member in the ejection mechanism 9 is used to passively eject the core 8, so that the top pressure spring 93 is compressed when the moving mold is reset and closed, and the top pressure spring 93 extends when the moving mold opens to drive the fixed mold ejector rod 21 to eject. The elastic potential energy of the spring is used to do work to push the fixed mold ejector rod 21 to push out the core 8, ensuring the synchronization of mold opening and the separation of the core 8 from the fixed mold. For the core mold adopting the ejection mechanism 9 of the present invention, it can basically ensure that the core 8 separates from the fixed mold and remains on the moving mold during mold opening under the condition of no auxiliary draft, and then falls from the moving mold onto the production line after the moving mold moves above the production line, ensuring the continuity of automated production and reducing the workload of manually removing the auxiliary draft.

[0066] The core mold of this embodiment, as Figure 2 、 Figure 3 and combined with Figure 7 shown, the moving mold includes a moving mold base 4, a substrate 53 for carrying the moving mold base 4 to move in the mold opening direction, and a driving device for driving the moving mold base 4 to open. Among them, a moving mold frame plate 40 and a moving mold middle frame plate 41 are arranged at intervals on the left and right of the moving mold base 4. The moving mold module 3 is fixedly installed on the side of the moving mold frame plate 40 facing the fixed mold. A guide rod 411 is provided on the side of the moving mold middle frame plate 41 facing away from the moving mold frame plate 40. The moving mold base 4 is arranged on the substrate 53 in a direction that can be guided by the guide rod 411.

[0067] Meanwhile, a moving die ejector rod 31 is inserted through the moving die module 3; the moving die ejector rod 31 is arranged along the mold opening direction, and one end of the moving die ejector rod 31 close to the fixed die extends to be flush with the inner wall of the moving die cavity 30; moreover, the mold opening movement path of the moving die base 4 includes a main movement section and a final section that are connected front and back. When the moving die base 4 moves to the final section, the substrate 53 can act on the moving die ejector rod 31 to drive the moving die ejector rod 31 into the moving die cavity 30 to eject the core 8 located in the moving die cavity 30.

[0068] By arranging the moving die ejector rod 31 on the moving die module 3, it is convenient to eject the core 8 from the moving die cavity 30 after the moving die moves to the mold opening position accurately and drop it onto the production line for subsequent processes. The driving device is used to drive the moving die base 4 to move in the mold opening direction, and the mold opening movement path of the moving die base 4 is divided into a main movement section and a final section; by designing a reasonable transmission structure between the substrate 53 and the moving die ejector rod 31 according to the length dimensions of the main movement section and the final section, the moving die ejector rod 31 can be blocked in the final section to realize the pushing movement of the moving die ejector rod 31 relative to the moving die base 4, so that the core 8 can be smoothly ejected from the moving die cavity 30 by the moving die ejector rod 31 in the final section. The above setting method does not require a separate driving mechanism for driving the moving die ejector rod 31 on the moving die, thus reducing the number of driving components.

[0069] In this embodiment, a moving die ejector rod seat is provided on the moving die base 4. The moving die ejector rod seat is located between the moving die mold plate 40 and the moving die middle plate 41, and the moving die ejector rod seat can move relative to the moving die base 4 in the mold opening direction. The moving die ejector rod seat and the moving die reset mechanism of this embodiment can be designed with reference to the existing structure. Specifically, the moving die ejector rod seat includes a fixed bottom plate 510 that is guidingly arranged on the moving die base 4. One end of the above-mentioned moving die ejector rod 31 and one end of the following moving die reset rod 32 away from the fixed die are both press-fitted and fixed on the fixed bottom plate 510 through a moving die ejector rod fixing plate 511 and a moving die ejector rod pressing plate 512.

[0070] Based on the above setting, a top column 54 extending towards the fixed die direction is provided on the substrate 53 of this embodiment. When the moving die base 4 moves to the final section, the top column 54 presses on the moving die ejector rod seat through a through hole 410 formed on the moving die middle plate 41 to drive the moving die ejector rod 31 into the moving die cavity 30. By providing a moving die ejector rod seat for fixedly installing each moving die ejector rod 31 on the moving die base 4, it is convenient for the fixed installation and arrangement of each moving die ejector rod 31; by using the top column 54 formed on the substrate 53 to push the moving die ejector rod seat, the driving of each moving die ejector rod 31 can be realized synchronously, so that each moving die ejector rod 31 performs the ejection action synchronously.

[0071] In addition, a moving die reset mechanism can be provided between the moving die module 3 and the moving die ejector rod base. The moving die reset mechanism of this embodiment includes a moving die reset spring 521 that can elastically act between the moving die module 3 and the moving die ejector rod base. Specifically, a second positioning post 520 is provided on the moving die ejector rod base, and the above-mentioned moving die reset spring 521 is sleeved on the second positioning post 520. The two ends of the moving die reset spring 521 act on the moving die ejector rod pressure plate 512 and the moving die mold base plate 40 respectively. When the moving die base 4 returns from the end section to the main moving section, the ejector pin 54 disengages from pressing against the moving die ejector rod base, and the moving die ejector rod 31 can retract under the action of the moving die reset spring 521 to a state where its end is flush with the inner wall of the moving die cavity 30.

[0072] After the moving die ejector rod 31 completes the ejection action of the sand core 8, when the substrate 53 releases the acting force on the moving die ejector rod 31 during the return of the moving die, the elastic force of the moving die reset spring 521 is used to drive the moving die ejector rod 31 to reset to a state where its end is flush with the inner wall of the moving die cavity 30, which can enable the moving die cavity 30 to enter the normal mold-forming state. When the moving die and the fixed die are closed, the injected sand material can be well molded in the core box, avoiding the situation where the end of the moving die ejector rod 31 affects the molding shape of the sand core 8.

[0073] In addition, as shown in Figure 2 this embodiment, the driving device preferably adopts a moving die driving oil cylinder 61. The moving die driving oil cylinder 61 is installed on the substrate 53, and the moving die driving oil cylinder 61 drives the moving die base 4 to move in the mold opening direction through the oil cylinder rod 610. When the moving die base 4 completes the entire mold opening movement path, the substrate 53 can be flipped under the drive of the flipping drive mechanism 55, so that the sand core 8 that has been ejected from the moving die cavity 30 by the moving die ejector rod 31 falls onto the production line.

[0074] For the sand injection sand box 7 required for the sand core mold, it can be set with reference to the existing sand core mold. In the closed mold state, the sand material in the sand injection sand box 7 flows out through the sand injection plate 70 at the bottom of the sand injection sand box 7 and is injected into the core box through the sand injection hole 71 provided on the fixed die module 2 or the moving die module 3 to form the sand core 8.

[0075] Similar to the function of the above-mentioned movable mold reset mechanism, preferably, a fixed mold reset rod 22 is also provided on the fixed mold module 2 of this embodiment, and the fixed mold reset rod 22 is arranged along the mold opening direction. The fixed mold reset rod 22 extends from one end close to the movable mold to the end surface of the fixed mold module 2, and the other end of the fixed mold reset rod 22 is transmission-connected to the fixed mold ejector rod 21. When the movable mold is closed onto the fixed mold, the movable mold module 3 can press the fixed mold reset rod 22, thereby driving the fixed mold ejector rod 21 to retract to a state where the end is flush with the inner wall of the fixed mold cavity 20. Similarly, a movable mold reset rod 32 is also provided on the movable mold module 3 of the present embodiment. The movable mold reset rod 32 is arranged along the mold opening direction. One end of the movable mold reset rod 32 close to the fixed mold extends to the end surface of the movable mold module 3, and the other end of the movable mold reset rod 32 is transmission-connected to the movable mold ejector rod 31. When the movable mold is closed onto the fixed mold, the fixed mold module 2 can press the movable mold reset rod 32, thereby driving the movable mold ejector rod 31 to retract until the end is flush with the inner wall of the movable mold cavity 30.

[0076] By respectively arranging a movable mold reset rod 32 and a fixed mold reset rod 22 on the movable mold and the fixed mold, with the aid of the abutment between the fixed mold module 2 and the movable mold module 3 when the mold is closed, the fixed mold reset rod 22 can drive the fixed mold ejector rod 21 to reset, and the movable mold reset rod 32 can drive the movable mold ejector rod 31 to reset, so that the ends of each ejector rod are flush with the inner wall of the core box, so that the core box enters a normal molding state, which makes it convenient for the injected sand material to be well molded in the core box, thereby ensuring the reliability of the operation of the sand core mold.

[0077] The sand core mold of the utility model solves the problem that it is difficult to synchronize the mold opening and the ejection from the fixed mold side, and ensures that the sand core 8 remains on the dynamic mold side when the core box is opened. The application of the sand core ejection mechanism can ignore the selection of the dynamic and static mold sides when the core box is parted during design, that is, the fixed mold moves relative to the dynamic mold to open the mold, which can also ensure that the sand core 8 is first detached from the fixed mold cavity 20. At the same time, the embedded spring design is adopted in the ejection mechanism 9, and the top pressure spring 93 can be flexibly arranged and springs with different elastic force specifications can be selected according to the different sizes of the sand core 8 in the narrow space between the equipment and the mold. It can be seen that the sand core mold of the utility model realizes the spring ejection function in a narrow space, realizes the absolute synchronization between the core box mold opening and the spring ejection, and ensures the continuity of the automated production line.

[0078] The above is only a preferred embodiment of the present invention. The detailed explanation of the configuration, the examples of the specific structural setting, or the description of the assembly connection method, etc., are all for the purpose of full disclosure so that those skilled in the art can better implement the present invention, and are not intended to limit the scope of protection of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A core ejection mechanism, characterized in that: It includes an ejection mechanism (9) provided on the fixed mold of the core mold; the fixed mold includes a fixed mold base (1) and a fixed mold module (2) provided on the side of the fixed mold base (1) facing the moving mold, and a fixed mold cavity (20) on the fixed mold module (2) and a moving mold cavity (30) on the moving mold module (3) of the moving mold form a core box for molding a core (8). The ejection mechanism (9) includes a fixed mold ejector rod (21) penetrating through the fixed mold module (2), and an elastic member acting between the fixed mold base (1) and the fixed mold ejector rod (21). The fixed mold ejector rod (21) is arranged along the mold opening direction of the moving mold, and one end of the fixed mold ejector rod (21) close to the moving mold extends to be flush with the inner wall of the fixed mold cavity (20). The elastic member applies an elastic force to the fixed mold ejector rod (21) in the mold opening direction. As the moving mold opens, the fixed mold ejector rod (21) can enter the fixed mold cavity (20) under the action of the elastic force to eject the core (8) located in the fixed mold cavity (20).

2. The core ejection mechanism according to claim 1, characterized in that: Corresponding to each fixed mold cavity (20), a plurality of the fixed mold ejector rods (21) are arranged at intervals on the fixed mold module (2).

3. The core ejection mechanism according to claim 1 or 2, characterized in that: The ejection mechanism (9) further includes an ejector rod base (90) and an ejector rod frame provided on the fixed mold base (1). The ejector rod base (90) is fixedly installed on the fixed mold base (1), and the ejector rod frame can move relative to the fixed mold base (1) in the mold opening direction; One end of the fixed mold ejector rod (21) away from the moving mold is fixedly connected to the ejector rod frame, and the elastic member acts between the ejector rod base (90) and the ejector rod frame.

4. The core ejection mechanism according to claim 3, characterized in that: A first positioning column (91) is fixedly provided on the side of the ejector rod base (90) facing the moving mold, and the first positioning column (91) is arranged along the mold opening direction; the elastic member includes a top pressure spring (93) sleeved on the first positioning column (91), and a spring cap (922) is sleeved outside the top pressure spring (93); the spring cap (922) is connected to the ejector rod frame, and the top pressure spring (93) transmits the elastic force to the fixed mold ejector rod (21) through the spring cap (922) and the ejector rod frame.

5. The core ejection mechanism according to claim 3, characterized in that: The ejector rod frame includes an ejector rod bottom plate (920) and an ejector rod pressing plate (921) stacked together. The end of the fixed mold ejector rod (21) for connecting the ejector rod frame is formed with a head with a radial protrusion. A groove for accommodating the head is provided on the ejector rod bottom plate (920), and the ejector rod pressing plate (921) presses the head in the groove so that the fixed mold ejector rod (21) is fixedly connected to the ejector rod frame.

6. A core mold, characterized in that: The fixed mold of the sand core mold is provided with a sand core ejection mechanism according to any one of claims 1 to 5.

7. The sand core mold according to claim 6, characterized in that: The movable mold comprises a movable mold base (4), a base plate (53) for carrying the movable mold base (4) to move in the mold opening direction, and a driving device for driving the movable mold base (4) to open the mold; The movable mold module (3) is arranged on a side of the movable mold base (4) facing the fixed mold, and a movable mold ejector rod (31) is passed through the movable mold module (3); the movable mold ejector rod (31) is arranged along the mold opening direction, and one end of the movable mold ejector rod (31) close to the fixed mold extends to be flush with the inner wall of the movable mold cavity (30); The mold opening movement path of the movable mold base (4) includes a main movement section and a terminal section connected front and rear. When the movable mold base (4) moves to the terminal section, the base plate (53) can act on the movable mold ejector rod (31) to drive the movable mold ejector rod (31) to enter the movable mold cavity (30) and eject the sand core (8) located in the movable mold cavity (30).

8. The sand core mold according to claim 7, characterized in that: A movable mold ejector seat is provided on the movable mold seat (4), and the movable mold ejector seat can move relative to the movable mold seat (4) in the mold opening direction; one end of the movable mold ejector (31) away from the fixed mold is fixedly connected to the movable mold ejector seat; The base plate (53) is provided with a push column (54) extending in the direction of the fixed mold. When the movable mold seat (4) moves to the end section, the push column (54) presses on the movable mold push rod seat to drive the movable mold push rod (31) into the movable mold cavity (30).

9. The sand core mold according to claim 8, characterized in that: A movable mold reset mechanism is provided between the movable mold module (3) and the movable mold ejector seat, and the movable mold reset mechanism comprises a movable mold reset spring (521) capable of elastically acting between the movable mold module (3) and the movable mold ejector seat; when the movable mold seat (4) returns from the end section to the main moving section, the movable mold ejector (31) can be retracted to a state where the end is flush with the inner wall of the movable mold cavity (30) under the action of the movable mold reset spring (521).

10. The sand core mold according to any one of claims 7 to 9, characterized in that: The fixed mold module (2) is also provided with a fixed mold reset rod (22), which is arranged along the mold opening direction, and one end of the fixed mold reset rod (22) close to the movable mold extends to the end surface of the fixed mold module (2), and the other end of the fixed mold reset rod (22) is transmission-connected to the fixed mold ejector rod (21). When the movable mold is closed onto the fixed mold, the movable mold module (3) can press the fixed mold reset rod (22), thereby driving the fixed mold ejector rod (21) to retract to a state where the end is flush with the inner wall of the fixed mold cavity (20); And / or, a moving die reset rod (32) is also penetrated through the moving die module (3). The moving die reset rod (32) is arranged along the mold opening direction. One end of the moving die reset rod (32) close to the fixed die extends to the end face of the moving die module (3). The other end of the moving die reset rod (32) is in transmission connection with the moving die ejector rod (31). When the moving die is closed onto the fixed die, the fixed die module (2) can press against the moving die reset rod (32), thereby driving the moving die ejector rod (31) to retract to a state where the end is flush with the inner wall of the moving die cavity (30).

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