Lightweight aluminum piston automatic casting machine

Abstract

The invention relates to the technical field of piston casting, in particular to an automatic casting machine for a light-weight aluminum piston, which is used for casting a piston blank with a positioning table and comprises a lower die, a left die, a right die, an upper die and a cooling cone, the left die slides on the left side of the lower die, the right die slides on the right side of the lower die, and the lower die is wrapped when the right die and the left die are attached. The upper die is inserted between the left die and the right die, a reference forming groove is formed in the upper die, the reference forming groove penetrates through the upper die, the reference forming groove and the upper die are coaxial, and the cooling cone is located above the upper die. According to the piston cooling forming device, by communicating molten metal with the outside and arranging the joint in a multi-stage mode, the purpose of exhausting gas in time is achieved, meanwhile, the piston cooling forming speed is increased, and the piston structure is optimized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of piston casting, in particular to an automatic casting machine for lightweight aluminum pistons. BACKGROUND

[0002] A piston is a reciprocating machine in a cylinder block, and its performance directly affects the output capacity of an engine, so with the increasing demand for various performances of automobiles, different types of pistons have been gradually developed, and lightweight aluminum pistons are one of them.

[0003] The production process of a cast piston includes blank casting and subsequent finishing, and during piston casting, a combined mold is generally used, a cavity with an opening upward is first formed by combining a plurality of fixed molds and movable molds, then a predetermined amount of molten metal is poured into the cavity, and then the mold located above the cavity is rapidly pressed down to form a forming space for the piston blank, after which the piston blank is taken out after cooling and forming for further processing.

[0004] However, when the mold is pressed down, the air inside the cavity will be continuously compressed, and since the pressed-down mold is in sliding sealing connection with other molds, the compressed gas cannot be discharged in time, which will cause the following consequences: first, part of the gas is mixed into the molten metal, resulting in a large number of gas bubbles in the molten metal, which in turn causes a large number of pores in the formed piston blank, thereby affecting the quality of the piston, second, the gas remains above the molten metal surface, causing the molten metal surface to be uneven, and in turn causing the end face of the formed piston blank to have a large number of burrs; and the lightweight aluminum piston itself has a thinner wall thickness (in order to reduce the quality, the wall thickness of the piston top, skirt and ring bank area is further reduced) and a more complex internal structure (in order to ensure structural strength and heat dissipation performance, complex internal cavity structures such as internal cooling oil channels and reinforcing ribs are generally used), which makes the "difficult to exhaust" problem more prominent, first, a large number of pores will further reduce the structural strength of the thin wall, second, the processing allowance of the burrs on the thin wall is further compressed, thereby increasing the processing difficulty.

[0005] Therefore, an automatic casting machine for lightweight aluminum pistons is proposed. SUMMARY

[0006] The present application aims to provide an automatic casting machine for lightweight aluminum pistons, which solves the problem of the inability to discharge gas in time from the piston casting cavity, and achieves the purpose of discharging gas in time by connecting the molten metal with the outside and setting multiple levels at the connection, while improving the speed of piston cooling and forming and optimizing the piston structure.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] The application discloses a light-weight aluminum piston automatic casting machine which is used for casting a piston blank with a positioning platform and comprises a lower mold, a left mold and a right mold, the left mold slides at the left side of the lower mold, the right mold slides at the right side of the lower mold, and the right mold and the left mold wrap the lower mold when being attached, and the machine further comprises an upper mold and a cooling cone, the upper mold is inserted between the left mold and the right mold, and the inner part of the upper mold is provided with a reference forming groove, the reference forming groove penetrates through the upper mold and is coaxial with the upper mold, and the cooling cone is located above the upper mold.

[0009] The left mold moves to the right, the right mold moves to the left to form a cavity containing metal liquid, the upper mold moves downwards to compress the metal liquid in the cavity and form a forming space of the piston blank, the reference forming groove contains the metal liquid which moves upwards under pressure and serves as a channel for discharging air bubbles, and the cooling cone contacts hot air which rises along the reference forming groove to accelerate the cooling of the piston blank.

[0010] The lower groove is used for forming the positioning platform, and the piston blank obtained through the casting process needs to be machined subsequently (since the piston blank is a rotary body structure, the subsequent machining is mostly assisted by a lathe) so as to obtain a final product, and in the machining, the lathe center needs a positioning reference, therefore, the end face of the piston is often machined to form a positioning groove as the positioning reference, but in the actual use process, the positioning groove can weaken the structural strength of the piston.

[0011] Preferably, the reference forming groove comprises an upper groove and a lower groove from top to bottom in sequence, and the sectional area of the upper groove is smaller than that of the lower groove.

[0012] Through the above scheme, the lower groove is used for forming the positioning platform, the positioning platform is used as a part of the piston blank in the machining, the positioning groove is formed on the positioning platform, the positioning platform is removed after the machining is completed, and after being heated and melted, the removed positioning platform can continue to be used as the raw material of the metal liquid to cast the piston blank; the upper groove is used for making the metal liquid which is immersed in the lower groove continue to surge upwards so as to increase the pressure of the metal liquid in the cavity below the upper mold, and then the casting pressure of the effective part (not including the positioning platform and the part above the positioning platform) of the piston blank is increased, thereby the structural strength of the piston blank is increased and the channel for releasing the air bubbles in the metal liquid is provided; since the closer to the liquid surface of the metal liquid, the smaller the pressure is, the air bubbles in the metal liquid will concentrate to the liquid surface and then break to release the gas.

[0013] Preferably, the lower groove is provided in a circular table structure, and the small diameter of the lower groove is on the top.

[0014] In the above scheme, the lower groove is provided as a circular truncated cone structure with a small diameter on top. On the one hand, the circular truncated cone structure as a rotary body is more convenient for later removal. On the other hand, compared with a cylindrical structure, the circular truncated cone structure effectively reduces the volume of the positioning table, thereby reducing the total amount of recycling of the positioning table, so that more molten metal directly participates in the effective part of the piston blank casting, thereby improving the production efficiency. In addition, the circular truncated cone structure can also make the positioning table more easily separated from the lower groove, thereby improving the demolding efficiency.

[0015] Preferably, the upper groove is provided as a circular truncated cone structure, and the large diameter of the upper groove is on the lower side. The large diameter of the upper groove is smaller than the small diameter of the lower groove, and the height of the upper groove is greater than the height of the lower groove.

[0016] In the above scheme, the upper groove is provided as a circular truncated cone structure, which also has the effects of promoting demolding, facilitating removal, and reducing the total amount of recycling. In addition, the upper groove can form a chimney effect by virtue of its height to accelerate the discharge of high-temperature gas in the molten metal, thereby reducing the residual amount of gas bubbles in the molten metal to make the formed piston blank have higher structural strength, and accelerating the cooling of the molten metal to accelerate the forming of the piston blank. Since there is a large length of the upper groove between the external cold source and the effective part of the piston blank, a certain temperature gradient is formed, thereby avoiding local quenching of the effective part of the piston blank, thereby ensuring the structural strength of the piston blank after forming.

[0017] The diameter of the upper groove should be as small as possible. On the one hand, the smaller the diameter of the upper groove, the smaller the volume, thereby reducing the total amount of recycling. On the other hand, the smaller the diameter of the upper groove, the higher the liquid level when the same amount of molten metal flows into the upper groove, thereby increasing the pressure of the molten metal in the cavity below the upper die, thereby increasing the structural strength of the effective part of the piston blank. However, as the diameter of the upper groove decreases, the diameter of the structure formed by the upper groove also decreases, and the structure will be quenched due to the chimney effect of the upper groove, thereby causing local fracture. Therefore, the demolding process of this part should be designed accordingly.

[0018] Preferably, the upper die comprises a fixed die and a movable die from top to bottom, the movable die is slidably connected to the fixed die, and the two movable dies are configured to be detachably connected. The upper groove is located inside the movable die, and the lower groove is located inside the fixed die.

[0019] Through the above scheme, when the structure formed by the upper groove is fractured and stuck inside the upper groove, the two movable dies can slide on the fixed die to split the upper groove in half, thereby removing the fractured part.

[0020] Preferably, the cooling cone is installed on the fixed die, and the cooling cone is provided as an inverted cone structure, and the cooling cone is coaxial with the lower groove.

[0021] In the above scheme, on the one hand, the hot gas discharged by the upper groove exchanges heat with the conical surface of the cooling cone to increase the cooling speed of the metal liquid, thereby improving the casting efficiency of the piston blank; on the other hand, the cooling cone is coaxial with the lower groove, that is, when the two movable molds are attached, the cooling cone is located directly above the upper groove, and the upper bottom surface of the cooling cone blocks external dust to ensure the purity of the mold.

[0022] Preferably, the cooling cone is hollow inside and filled with cooling liquid to further improve the cooling performance of the cooling cone.

[0023] Preferably, the cooling cone is provided with an inlet pipe and an outlet pipe, the outlet of the inlet pipe is below the inlet of the outlet pipe, so that the cooling liquid discharged from the inlet pipe is concentrated in the tip part of the cooling cone first, thereby improving the heat exchange effect of the cooling cone and the hot air discharged by the upper groove, and the heated cooling liquid rises and is discharged from the inlet of the outlet pipe.

[0024] Adjustment of the composition and proportion of the metal liquid usually has different requirements for the cooling process of the metal liquid.

[0025] Preferably, the cooling cone is slidingly connected to the fixed mold, and different refrigeration effects are achieved by adjusting the height of the cooling cone.

[0026] Compared with the prior art, the present application has the following advantages:

[0027] 1. The present application sets a through reference forming groove in the upper mold and sets a cooling cone above it, thereby constructing a channel connecting the casting cavity and the outside, which can smoothly discharge the compressed gas in the cavity and the gas bubbles mixed into the metal liquid, thereby solving the problems of pores in the piston blank and burrs on the end face caused by the inability to discharge gas in the background art, and significantly improving the compactness and quality of the piston casting; at the same time, the cooperation of the cooling cone and the channel accelerates the cooling and forming of the piston and improves the production efficiency.

[0028] 2. The reference forming groove of the present application includes an upper groove and a lower groove, wherein the upper groove with small cross-sectional area and large height not only forms a "chimney effect" to accelerate the discharge of hot gas, but more importantly, it can throttle and hinder the metal liquid entering the reference forming groove, thereby greatly increasing the pressure of the metal liquid in the lower main cavity, making the final formed piston effective part more compact and having higher structural strength, and the positioning table formed by the lower groove serves as a temporary reference for subsequent finishing of the piston blank, which can be removed and recycled after finishing, avoiding the problem of weakening the final structural strength of the piston body by setting a permanent positioning groove on the piston body, and realizing the unity of casting quality optimization and processing convenience.

[0029] 3、The cooling cone in the application carries out high-efficiency heat exchange on the high-temperature gas discharged from the upper groove through the internally circulating cooling liquid, improves the cooling speed and shortens the production cycle, and also makes the slender metal rod formed in the upper groove brittle due to the quenching, and correspondingly, the application guarantees that the brittle metal rod can be reliably taken out through the design of the upper die, and once the metal rod is broken and stuck in the upper groove, the broken part can be easily taken out by separating the movable die, effectively solves the die sticking problem possibly caused by the exhaust structure, and enhances the reliability of the equipment operation and the stability of the continuous production. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is the whole isometric structure schematic diagram of the application;

[0031] Figure 2 It is the whole internal structure schematic diagram of the application;

[0032] Figure 3 It is the casting piston state schematic diagram of the application;

[0033] Figure 4 It is the movable die of the application; Figure 3 It is the enlarged schematic diagram of A part of the application;

[0034] Figure 5 It is the internal structure schematic diagram of the fixed die of the application;

[0035] Figure 6 It is the movable die opening state schematic diagram of the application;

[0036] Figure 7 It is the cooling cone structure schematic diagram of the application;

[0037] Figure 8 It is the piston blank first separation state schematic diagram of the application;

[0038] Figure 9 It is the piston blank second separation state schematic diagram of the application.

[0039] In the drawing: 1, lower die; 2, left die; 3, right die; 4, upper die; 41, reference forming groove; 411, upper groove; 412, lower groove; 42, fixed die; 43, movable die; 5, cooling cone; 51, cooling liquid; 52, liquid inlet pipe; 53, liquid outlet pipe; 6, piston blank; 61, positioning table. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0041] Please refer to Figures 1 to 9 The present application provides a light-weight aluminum piston automatic casting machine, and the technical solutions are as follows.

[0042] Referring to Figures 1 to 6 A light-weight aluminum piston automatic casting machine is used to cast a piston blank 6 with a positioning table 61, and comprises a lower mold 1, a left mold 2, a right mold 3, an upper mold 4 and a cooling cone 5. In operation, the lower mold 1 is fixed on a platform, the left mold 2 slides left and right on the left side of the lower mold 1 under the push and pull of a cylinder, the right mold 3 slides left and right on the right side of the lower mold 1 under the push and pull of a cylinder, the inner groove of the left mold 2 tightly abuts against the flange of the lower mold 1 when the left mold 2 slides to the limit position to the right, the inner groove of the right mold 3 tightly abuts against the flange of the lower mold 1 when the right mold 3 slides to the limit position to the left, and the grooves of the left mold 2 and the right mold 3 are in close contact with the flange of the lower mold 1, so that the left mold 2, the right mold 3 and the lower mold 1 jointly form a cavity with an open upper end and a sealed rest. The upper part of the lower mold 1 has irregular protrusions, which are the internal shape of the piston blank 6 and can be changed according to actual requirements. Then, the molten metal is poured into the cavity from the opening at the upper end. In order to ensure the consistency of the piston blanks 6 cast in the same batch, the total amount of molten metal poured each time should be consistent. Specifically, a mechanical arm can be used to hold a crucible with a specified capacity, and then a specified amount of molten metal is scooped from the molten pool and poured into the mold cavity. Then, the cylinder pushes the upper mold 4 to move downward between the left mold 2 and the right mold 3, and the upper mold 4 is provided with a reference forming groove 41. The reference forming groove 41 penetrates through the upper mold 4 and is coaxial with the upper mold 4. The upper mold 4 moves downward by a rated height to give the molten metal in the cavity a rated pressure, so that the structure of the formed piston blank 6 is more compact and the strength is higher. The cooling cone 5 is located above the upper mold 4. In the above scheme, the action sequence and stroke of the three cylinders (i.e. the left mold 2 cylinder, the right mold 3 cylinder and the upper mold 4 cylinder) are controlled by a PLC controller according to a preset program, so as to realize the automatic opening and closing of the mold and die casting in the automatic casting machine.

[0043] The left mold 2 moves to the right, the right mold 3 moves to the left to form a cavity containing molten metal, the upper mold 4 moves downward to compress the molten metal in the cavity and form a forming space of the piston blank 6, the reference forming groove 41 contains the molten metal that moves upward under pressure and serves as a channel for the upward discharge of air bubbles, and the cooling cone 5 contacts the hot air that rises along the reference forming groove 41 to accelerate the cooling of the piston blank 6.

[0044] As an embodiment of the present application, referring to Figure 5The reference forming groove 41 comprises an upper groove 411 and a lower groove 412 from top to bottom, and the sectional area of the upper groove 411 is smaller than that of the lower groove 412;

[0045] When the upper die 4 is pressed down by the cylinder thrust, the outer periphery of the upper die 4 is sealed with the left die 2 and the right die 3 through the sealing ring to prevent the molten metal from flowing out from the gap between the upper die 4 and the left die 2 or the right die 3, and the lower end surface of the upper die 4 is first contacted with the molten metal during the pressing process of the upper die 4, then the molten metal enters the lower groove 412 and then enters the upper groove 411 with the continuous pressing of the upper die 4, and the pressure of the molten metal in the cavity below the upper die 4 gradually increases with the continuous lifting of the liquid level in the upper groove 411, which can also be verified in the reverse direction that whether the molten metal poured into the cavity is equal each time: when the piston blanks 6 of the same batch are cast, the height of the upper die 4 is consistent, that is, the liquid level height in the upper groove 411 should also be consistent under the premise of pouring equal molten metal, and thus the piston blanks 6 after forming are compared, if the lengths of the structures formed in the upper groove 411 are inconsistent, it means that the total amount of molten metal poured is different;

[0046] The sectional area of the upper groove 411 should be as small as possible, on the one hand, the smaller the sectional area of the upper groove 411, the smaller the volume, thereby reducing the total amount of recovery, on the other hand, the smaller the sectional area of the upper groove 411, the higher the liquid level when the same amount of molten metal flows into the upper groove 411, thereby the pressure of the molten metal in the cavity below the upper die 4 is higher, so that the structural strength of the effective part of the piston blank 6 is higher; and in the drawings of the present scheme, the upper groove 411 is enlarged for clearer display of the structure thereof.

[0047] As an embodiment of the present application, referring to Figure 4 and Figure 6 The upper die 4 comprises a fixed die 42 and a movable die 43 from top to bottom, the movable die 43 is connected with the slide rail structure of the fixed die 42 through the slide block structure of the movable die 43; when installed, the slide block below the movable die 43 is inserted into the slide rail from the outer edge of the fixed die 42, and the movable die 43 moves inwardly and contacts the terminal surface of the slide rail to reach the limit position, and the two movable dies 43 are just fitted when they are at the limit position, at this time, the bolt is inserted into the through hole of the boss of the movable die 43 to fasten the two movable dies 43, and the position of the movable die 43 is bound with the fixed die 42 and no longer slips; the two movable dies 43 are detachably connected through the disassembly and assembly of the bolt, the upper groove 411 is located in the movable die 43, and the lower groove 412 is located in the fixed die 42;

[0048] Generally, the two movable dies 43 are attached to each other by means of bolts passing through the through holes on the protrusions of the movable dies 43, at this time, the upper groove 411 inside the movable die 43 and the lower groove 412 inside the fixed die 42 are continuous cavities, when the upper die 4 is pressed down, the molten metal enters the lower groove 412 and the upper groove 411 in turn, and after the piston blank 6 is cooled and formed, the upper die 4 is lifted up, and the upper die 4 is in turn separated from the structure formed by the upper groove 411 and the positioning table 61; it can be known from the above analysis that the cross-sectional area of the upper groove 411 should be as small as possible, but the smaller the cross-sectional area is, the more likely it is to break and be stuck inside the upper groove 411, therefore, when the upper die 4 is lifted up and stuck (the phenomenon is that the upper die 4 is difficult to lift up when the left die 2 and the right die 3 are not separated, or the piston blank 6 is lifted up together with the upper die 4 when the left die 2 and the right die 3 are separated), the bolts fastening the movable dies 43 are removed to separate the two movable dies 43, so that the broken structure stuck inside the upper groove 411 is removed to restore the normal operation of the automatic casting machine.

[0049] As an embodiment of the present application, referring to Figure 5 and Figure 8 , the upper groove 411 is provided in a circular truncated cone structure, and the large diameter of the upper groove 411 is above, the large diameter of the upper groove 411 is smaller than the small diameter of the lower groove 412, and the height of the upper groove 411 is greater than the height of the lower groove 412;

[0050] The structure formed by the upper groove 411 should be an elongated rod, first, the thinner it is, the less molten metal it occupies, thereby improving the direct utilization rate of the molten metal, and the thinner it is, the easier it is to remove the formed structure from the positioning table 61; the longer it is, the greater the pressure of the molten metal in the cavity below the upper die 4, thereby the better the quality of the cast piston blank 6, and the longer it is, the better the "chimney effect" formed by the upper groove 411; therefore, in order to obtain an elongated rod-shaped formed structure, the diameter of the upper groove 411 should be as small as possible, and the height should be as long as possible; in this embodiment, the diameter of the cast piston blank 6 is 42 mm, and the height (excluding the positioning table 61 and the structure above the positioning table 61) is 52 mm, the large diameter of the upper groove 411 is 2 mm, the small diameter is 1 mm, and the height is 20 mm; referring to Figure 8 After the cast piston blank 6 is taken out (usually using a clamping material taking mechanism) and completely cooled, the structure formed by the upper groove 411 on the protrusion is removed using a lathe or a shearing machine, and the removed structure is sent back to the molten pool for recycling, and a positioning groove is machined on the positioning table 61 to cooperate with the nail tip of the lathe in subsequent processing.

[0051] As an embodiment of the present application, referring to Figure 5 and Figure 9 , the lower groove 412 is provided in a circular truncated cone structure, and the small diameter of the lower groove 412 is above;

[0052] The fixed mold 42 is made of cast iron and a section is turned from a cylindrical blank as a fixed mold 42 blank. The processing is mainly carried out in three aspects. First, the diameter of a section of the fixed mold 42 blank is reduced by using a lathe to obtain a boss on the upper part of the fixed mold 42. Then, the lower groove 412 is processed. A through hole with a diameter equal to the small diameter of the lower groove 412 is drilled by using a drill press, and then the through hole is reamed by using a tapered reamer to obtain the complete lower groove 412. Finally, the slide rail on the fixed mold 42 that cooperates with the movable mold 43 is processed by using a milling machine. The main function of the positioning table 61 is to replace the end face of the piston and cooperate with the pin of the lathe. After the piston blank 6 is processed, the positioning table 61 is removed by using the lathe (see Figure 9 ) for details.

[0053] As an embodiment of the present application, referring to Figure 6 and Figure 7 , the cooling cone 5 is provided with a through hole in the up-down direction to be sleeved on the support of the fixed mold 42 to slide, and nuts are installed above and below the through hole to position the height of the cooling cone 5. The cooling cone 5 is arranged in an inverted cone structure, and the cooling cone 5 is coaxial with the lower groove 412.

[0054] As an embodiment of the present application, referring to Figure 7 , the cooling cone 5 is hollow inside, and the cooling cone 5 is filled with cooling liquid 51. The side wall of the cooling cone 5 is provided with a through hole to insert the liquid inlet pipe 52 and the liquid outlet pipe 53. Compared with the liquid outlet pipe 53, the liquid inlet pipe is inserted deeper so that the cooling liquid 51 enters the cooling cone 5 at the tip part to make the temperature of the outlet on the upper groove 411 lower, thereby promoting the “chimney effect” formed by the upper groove 411 to accelerate the discharge of hot gas in the metal liquid and increase the heat exchange speed between the metal liquid and the outside, so that the piston blank 6 is formed faster.

[0055] Working principle: In order to solve the problem that the gas in the cavity cannot be discharged during the casting of the piston blank 6, resulting in defects such as pores and burrs in the finished product, and at the same time improve the compactness and cooling efficiency of the casting, the specific way is to open a through reference forming groove 41 in the upper mold 4 as an exhaust and pressurization channel, and a cooling cone 5 is arranged directly above it. During casting, the gas in the cavity will be discharged from the reference forming groove 41, thereby realizing the release of the gas; at the same time, the cooling cone 5 quickly cools the discharged high-temperature gas, thereby accelerating the cooling forming speed of the entire piston blank 6, realizing the synchronous improvement of the casting quality and production efficiency.

[0056] In order to optimize the strength of the piston structure while taking into account the convenience of subsequent finishing, the specific way is to design the reference forming groove 41 as a two-stage structure composed of the lower groove 412 and the upper groove 411. The lower groove 412 is used to cast an additional temporary positioning table 61 on the top of the piston blank 6, which is used for centering and fixing during subsequent lathe processing. After processing, it can be turned off and recycled, thereby avoiding weakening the structure by machining a permanent positioning groove on the piston body. The upper groove 411 connected above the lower groove 412 has a smaller cross-sectional area and plays a key role in throttling and pressurizing. When the metal liquid is pressed into the reference forming groove 41, the narrow channel of the upper groove 411 significantly increases the metal liquid pressure in the main cavity below, making the final formed piston effective part more dense and having better mechanical properties.

[0057] In order to further strengthen the exhaust and cooling effect and ensure long-term stable operation of the equipment, the specific way is to design the structure of the upper groove 411, the configuration of the cooling cone 5 and the demolding mechanism of the upper die 4 in coordination. First, the upper groove 411 is designed as an elongated rod, and the "chimney effect" formed by its height can strengthen the convective exhaust efficiency of hot gas. Second, the cooling cone 5 is filled with circulating cooling liquid 51, which can efficiently and forcibly cool the high-temperature gas discharged from the upper groove 411, greatly shortening the casting cycle. However, this rapid cooling can also cause the brittle elongated metal rod solidified in the upper groove 411 to break during demolding. To solve this potential problem, the upper die 4 is designed as a combination structure of the fixed die 42 and the detachable movable die 43, and the upper groove 411 is located inside the movable die 43. Once the metal rod breaks and gets stuck, the two movable dies 43 can be separated to easily remove the broken material, avoiding long-term shutdown for maintenance, thereby ensuring the continuity and reliability of the entire automatic casting system production.

[0058] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A lightweight aluminum piston automatic casting machine for casting a piston blank (6) with a positioning platform (61), comprising a lower die (1), a left die (2) and a right die (3), the left die (2) sliding on the left side of the lower die (1), the right die (3) sliding on the right side of the lower die (1), and the right die (3) and the left die (2) wrapping the lower die (1) when they are closed, characterized in that: The application also comprises an upper die (4) and a cooling cone (5), the upper die (4) is inserted between the left die (2) and the right die (3), and the upper die (4) is internally provided with a reference forming groove (41), the reference forming groove (41) penetrates the upper die (4) and is coaxial with the upper die (4), and the cooling cone (5) is located above the upper die (4); the left die (2) moves to the right and the right die (3) moves to the left to form a cavity containing molten metal, the upper die (4) moves downward to compress the molten metal in the cavity and form a forming space of the piston blank (6), the reference forming groove (41) contains the upwardly compressed molten metal and serves as a channel for the upward discharge of air bubbles, and the cooling cone (5) contacts hot air rising along the reference forming groove (41) to accelerate the cooling of the piston blank (6).

2. The lightweight aluminum piston auto-casting machine according to claim 1, characterized in that: The reference forming groove (41) comprises an upper groove (411) and a lower groove (412) from top to bottom, and the cross-sectional area of the upper groove (411) is smaller than that of the lower groove (412).

3. The lightweight aluminum piston auto-casting machine according to claim 2, characterized in that: The lower groove (412) is in the shape of a circular truncated cone, and the small diameter of the lower groove (412) is on the top.

4. The lightweight aluminum piston auto-casting machine according to claim 3, characterized in that: The upper groove (411) is in the shape of a circular truncated cone, and the large diameter of the upper groove (411) is on the bottom, the large diameter of the upper groove (411) is smaller than the small diameter of the lower groove (412), and the height of the upper groove (411) is greater than that of the lower groove (412).

5. The lightweight aluminum piston auto-casting machine according to claim 4, characterized in that: The upper die (4) comprises a fixed die (42) and a movable die (43) from top to bottom, the movable die (43) is slidably connected to the fixed die (42), and the two movable dies (43) are detachably connected, the upper groove (411) is located in the movable die (43), and the lower groove (412) is located in the fixed die (42).

6. The lightweight aluminum piston auto-casting machine according to claim 5, characterized in that: The cooling cone (5) is mounted on the fixed die (42), and the cooling cone (5) is in the shape of an inverted cone and is coaxial with the lower groove (412).

7. The lightweight aluminum piston auto-casting machine according to claim 6, characterized in that: The cooling cone (5) is hollow inside and filled with a cooling liquid (51).

8. The lightweight aluminum piston auto-casting machine according to claim 7, characterized in that: The cooling cone (5) is internally provided with an inlet pipe (52) and an outlet pipe (53), and the outlet of the inlet pipe (52) is below the inlet of the outlet pipe (53).

9. The lightweight aluminum piston auto-casting machine of claim 6, wherein: The cooling cone (5) is slidably connected to the fixed die (42).

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