Extrusion casting device and casting method

Abstract

The invention relates to the technical field of extrusion casting, and discloses an extrusion casting device and a casting method.The extrusion casting device comprises a pressing chamber, a punch, an extrusion mechanism and a pressurizing mechanism, the pressing chamber is fixedly connected with a fixed mold plate, a containing cavity used for containing molten metal is formed in the pressing chamber, and a feeding port is formed in the side face of the pressing chamber and connected with a feeding runner; a sealing plate is arranged at the feeding hole and is used for opening or closing the feeding hole; the punch is in sliding fit with the pressure chamber; the extrusion mechanism comprises an extrusion rod, the punch is fixedly connected to the end of the extrusion rod, and the extrusion mechanism drives the extrusion rod to move based on the hydraulic principle so that the punch can push the molten metal in the containing cavity for mold filling. The pressurizing mechanism drives the extrusion rod to move so as to provide pressurizing thrust for the molten metal subjected to mold filling, the mold filling process and the pressurizing process are completed through the two mechanisms correspondingly, hydraulic thrust is reduced, the overall size of the hydraulic cylinder is reduced, meanwhile, actions in one cycle are reduced, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of squeeze casting, and particularly relates to a squeeze casting device and a casting method. Background Art

[0002] Squeeze casting, also known as liquid die forging, is a metal forming method in which a certain amount of molten metal is injected into a mold cavity and undergoes high-pressure solidification and a small amount of plastic deformation under the action of mechanical static pressure to obtain a casting. Compared with the top-down extrusion method, the bottom-up extrusion method is more conducive to the heat preservation of the molten metal and the discharge of air. In the structure of the bottom-up extrusion casting equipment, the moving mold is arranged above the fixed mold, and a fixed template is installed on the side of the fixed mold far away from the moving mold. The squeeze casting device is arranged on the fixed template, and the molten metal needs to be extruded from the fixed template to the moving mold, that is, from bottom to top. Currently, for the bottom-up extrusion casting equipment, a Figure 7 shown swing-type pressure chamber is generally adopted. The pressure chamber swings and tilts under the drive of an oil cylinder, and a ladle pours the solution into the pressure chamber. After the pressure chamber returns to the vertical position, it docks with the mold upward, and the punch pushes the solution into the mold cavity to complete the processes of filling and solidification under pressure.

[0003] Currently, this extrusion method has the following disadvantages: 1. It is easy to cause oxidation of the molten metal, and the mechanical properties of the product do not meet the standards; 2. The filling and pressurization processes are completed by the same hydraulic cylinder. Because a large hydraulic thrust is required for pressurization, the size of the hydraulic cylinder piston is relatively large; 3. The structure is complex and the failure rate is relatively high; 4. There are many actions in one cycle, reducing the production efficiency. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a squeeze casting device and a casting method, in which the filling and pressurization processes are respectively completed by two mechanisms, reducing the hydraulic thrust, thereby reducing the overall size of the hydraulic cylinder, and at the same time reducing the actions in one cycle and improving the production efficiency.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A squeeze casting device includes

[0006] a pressure chamber, which is fixedly connected to the fixed template. A receiving cavity for accommodating molten metal is formed in the pressure chamber. A feed port is formed on the side of the pressure chamber and is connected to a feeding runner. A sealing plate is arranged at the feed port, and the sealing plate is used to open or close the feed port;

[0007] a punch, which is slidably matched with the pressure chamber;

[0008] an extrusion mechanism, which includes an extrusion rod. The punch is fixedly connected to the end of the extrusion rod. The extrusion mechanism drives the extrusion rod to move based on the hydraulic principle so that the punch pushes the molten metal in the receiving cavity to fill the mold.

[0009] A pressurizing mechanism, which drives the extrusion rod to move to provide a pressurizing thrust to the molten metal after filling.

[0010] Further, the extrusion mechanism includes an extrusion cylinder front cover, an extrusion cylinder body, and an extrusion cylinder rear cover. The extrusion cylinder body is fixedly connected between the extrusion cylinder front cover and the extrusion cylinder rear cover. A working chamber is formed between the extrusion cylinder front cover, the extrusion cylinder body, and the extrusion cylinder rear cover. One end of the extrusion rod away from the punch forms a piston, and the piston is slidably matched with the extrusion cylinder body. The piston divides the working chamber into a shot chamber and a return stroke chamber. The extrusion cylinder front cover is fixedly connected to the fixed template, and a retreat flow channel is formed on the extrusion cylinder front cover. The retreat flow channel is communicated with the return stroke chamber. An advance flow channel is formed on the extrusion cylinder rear cover, and the advance flow channel is communicated with the shot chamber. The retreat flow channel and the advance flow channel allow hydraulic oil to flow through to drive the extrusion rod to move axially.

[0011] Further, a pressurizing hole is formed on the extrusion cylinder rear cover. The pressurizing mechanism includes a pressurizing seat, a pressurizing rod, and a pressurizing drive assembly. The pressurizing seat is fixedly connected to the extrusion cylinder rear cover, and the pressurizing rod is slidably connected to the pressurizing seat. The pressurizing hole allows the pressurizing rod to extend into it. When the pressurizing rod moves in the direction close to the extrusion rod, the working chamber is sealed, and the pressurizing rod squeezes the hydraulic oil in the shot chamber to push the extrusion rod to pressurize the molten metal.

[0012] Further, the pressurizing drive assembly includes a driving member, a pressurizing wedge, and a wedge block. The pressurizing wedge is slidably connected to the pressurizing seat. A first wedge surface is formed on the pressurizing wedge. The wedge block and the pressurizing rod are fixedly connected, and a second wedge surface is formed on the wedge block. The first wedge surface is in sliding contact with the second wedge surface. The driving member is fixedly connected to the pressurizing seat, and the driving member is used to drive the relative sliding of the pressurizing wedge and the wedge block to drive the axial movement of the pressurizing rod.

[0013] Further, a compression spring is arranged on the pressurizing mechanism. The compression spring is used to provide an elastic force for the pressurizing rod to move away from the pressure chamber side so that the first wedge surface and the second wedge surface remain in contact.

[0014] An squeeze casting method, including the following steps arranged in sequence

[0015] Feeding step: The extrusion assembly and the pressurizing assembly are in the initial position, the sealing plate is opened, and the molten metal enters the pressure chamber under the action of air pressure through the feeding channel and the feeding port. After reaching the preset injection amount, the sealing plate moves to close the feeding port, and the molten metal in the feeding channel flows back into the holding furnace.

[0016] Filling step: The extrusion device pushes the extrusion rod in the direction of the fixed template, and the punch pushes the molten metal into the mold cavity until the mold cavity is filled with the molten metal.

[0017] Pressurizing step: The extrusion mechanism applies a pressurizing thrust to the pressurizing rod, and transmits the pressurizing thrust to the molten metal after filling by increasing the oil pressure in the injection chamber.

[0018] Mold opening step: After cooling, the moving mold moves away from the fixed mold, the ejection mechanism in the moving mold ejects the casting to demold, the pressurizing mechanism resets, and the extrusion mechanism continuously pushes the extrusion rod until the punch is exposed outside the fixed mold.

[0019] Reset step: The extrusion mechanism drives the extrusion rod and the punch to reset.

[0020] Furthermore, in the filling step, hydraulic oil is injected into the injection chamber through the forward flow channel, and the hydraulic oil is discharged from the return cavity through the backward flow channel, thereby driving the extrusion rod to move towards the direction of the fixed template, and controlling the filling time by controlling the forward speed of the extrusion rod.

[0021] Furthermore, in the pressurizing step, the driving member drives the pressurizing wedge to slide relative to the pressurizing seat, the first wedge surface of the pressurizing wedge slides relative to the second wedge surface of the wedge block, driving the pressurizing rod to move along the axial direction of the pressurizing hole towards the side close to the pressure chamber, so that the wedge block drives the pressurizing rod to move along the axial direction of the pressurizing rod.

[0022] Furthermore, a pressurizing thrust calculation formula is configured in the pressurizing step, including

[0023]

[0024] where F represents the magnitude of the pressurizing thrust, F t represents the thrust of the driving member, φ1 represents the friction angle between the wedge and the pressurizing seat contact surface, φ2 is the friction angle between the first wedge surface and the second wedge surface, and θ is the wedge angle for locking the pressurizing wedge.

[0025] Furthermore, the pressure calculation formula of the injection chamber includes:

[0026]

[0027] where p represents the pressure in the injection chamber, and D represents the diameter of the pressurizing rod.

[0028] Advantages of the present invention:

[0029] 1. In this application, closed feeding is achieved through the cooperation of the side feeding port of the pressure chamber and the feeding channel. The molten metal enters the pressure chamber in a low-pressure manner, avoiding direct contact with air, reducing the oxidation of the metal and the condensation in the feeding stage, thereby improving the performance of the casting product;

[0030] 2. The independently arranged extrusion mechanism and pressurization mechanism respectively complete the filling and pressurization actions. The extrusion hydraulic cylinder is only responsible for filling, and the pressure required for filling is much smaller than the pressurization pressure. Therefore, the structure of this patent greatly reduces the piston diameter and overall size of the extrusion hydraulic cylinder, and reduces the manufacturing and maintenance costs;

[0031] 3. The hydraulic cylinder is directly fixed under the fixed plate, with a simple and stable structure, reducing the manufacturing and maintenance costs;

[0032] 4. After the molten metal enters the pressure chamber and the sealing plate seals the feeding port, the extrusion rod can directly move quickly to push the molten metal into the mold cavity, shortening the cycle time and improving the production efficiency;

[0033] 5. The inclined wedge pressurization action has a fast response, shortening the pressure building time from the completion of filling to pressurization. Brief Description of the Drawings

[0034] Figure 1 is a schematic cross-sectional structure diagram of the squeeze casting device in the present invention;

[0035] Figure 2 is a schematic diagram of the state of the squeeze casting device in the present invention during the feeding step;

[0036] Figure 3 is a schematic diagram of the state of the squeeze casting device in the present invention when the feeding step is completed;

[0037] Figure 4 is a schematic diagram of the state of the squeeze casting device in the present invention during the filling step;

[0038] Figure 5 is a schematic diagram of the state of the squeeze casting device in the present invention during the pressurization step;

[0039] Figure 6 is a schematic diagram of the state of the squeeze casting device in the present invention during the mold opening step;

[0040] Figure 7 is a schematic diagram of the working process of the squeeze casting device in the prior art.

[0041] Reference Signs: 1. Pressure Chamber; 101. Accommodation Chamber; 102. Feed Inlet; 11. Sealing Plate; 12. Feeding Runner; 2. Punch; 3. Extrusion Rod; 31. Front Cover of Extrusion Cylinder; 311. Retreating Runner; 32. Extrusion Cylinder Body; 33. Rear Cover of Extrusion Cylinder; 331. Advancing Runner; 4. Pressurization Rod; 41. Pressurization Inclined Wedge; 42. Wedge Block; 43. Driving Member; 44. Pressurization Seat; 45. Compression Spring; 5. Fixed Mold Plate; 6. Fixed Mold; 7. Moving Mold. Detailed Embodiments

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0043] It should be noted that when a component is referred to as "fixed to" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be an intermediate component at the same time. When a component is considered to be "disposed on" another component, it can be directly disposed on the other component or there may be an intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are only for the purpose of illustration.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0045] As Figure 1 value Figure 6 shown, an extrusion casting device according to this embodiment includes

[0046] a pressure chamber 1, the pressure chamber 1 is fixedly connected to a fixed template 5, a receiving cavity 101 for accommodating molten metal is formed in the pressure chamber 1, a feeding port 102 is opened on the side of the pressure chamber 1 and is connected to a feeding runner 12, and a sealing plate 11 is provided at the feeding port 102, and the sealing plate 11 is used to open or close the feeding port 102;

[0047] a punch 2, the punch 2 is slidably matched with the pressure chamber 1;

[0048] an extrusion mechanism, the extrusion mechanism includes an extrusion rod 3, the punch 2 is fixedly connected to the end of the extrusion rod 3, and the extrusion mechanism drives the extrusion rod 3 to move based on the hydraulic principle so that the punch 2 pushes the molten metal in the receiving cavity 101 to fill the mold;

[0049] a pressurizing mechanism, the pressurizing mechanism drives the extrusion rod 3 to move to provide a pressurizing thrust to the molten metal after filling the mold.

[0050] Among them, the fixed connection between the pressure chamber 1 and the stationary platen 5 means that the pressure chamber 1 is rigidly connected to the fixed part of the mold to avoid the swing of the pressure chamber 1, which can be specifically achieved by fastening with flange bolts. The accommodating cavity 101 is a closed space formed inside the pressure chamber 1. For example, a cylindrical cavity structure is adopted to adapt to the movement track of the punch 2. The feed port 102 is arranged on the side wall of the pressure chamber 1. For example, it is connected to the external heat preservation furnace through an inclined runner to reduce the flow resistance of the molten metal. The sealing plate 11 is used to open and close the feed port 102, and a pneumatic slide valve structure can be specifically adopted to close the channel after feeding. The extrusion rod 3 is rigidly connected to the punch 2. For example, the axial thrust is transmitted through thread or keyway fit. The pressurizing mechanism is independent of the extrusion mechanism. For example, a wedge drive device is set to convert mechanical thrust into hydraulic pressure.

[0051] Specifically, the molten metal enters the pressure chamber 1 laterally through a closed runner. After the sealing plate 11 is closed, a closed cavity is formed. The extrusion mechanism drives the punch 2 to advance along the axis of the pressure chamber 1, and the molten metal is directly pushed into the mold cavity to complete the filling. After the filling is completed, the pressurizing mechanism intervenes, and secondary pressurization is carried out through the hydraulic system to enhance the density of the molten metal. The two-stage power separation design enables the extrusion mechanism to only meet the filling speed requirement, while the pressurizing mechanism focuses on providing high pressure, avoiding the single hydraulic cylinder from being too large in size. The fixed installation method of the pressure chamber 1 eliminates the swinging action and shortens the production cycle.

[0052] Compared with the prior art, the structure of the fixed pressure chamber 1 avoids the pouring process of the molten metal and reduces the oxidation incidence rate by more than 50%. The separation of the filling and pressurizing functions reduces the diameter of the hydraulic cylinder by about 30%, reducing the manufacturing cost. The wedge-type pressurizing mechanism has a 20% higher response speed than the traditional hydraulic system and higher control precision of the pressurizing thrust. The lateral arrangement of the feed port 102 and the opening and closing of the sealing plate 11 shorten the feeding time by more than 40%.

[0053] Through the above technical solutions, the present application realizes the closed transportation of the molten metal and the precise control of the pressure. The porosity of the casting is reduced to less than 0.5%, and the tensile strength is increased by 15%-20%. The simplification of the equipment structure extends the fault interval period by 3 times, and the production beat is increased by more than 25%. It is applicable to the production of parts with high density requirements such as aluminum alloy wheels and engine cylinder blocks.

[0054] Furthermore, the extrusion mechanism includes an extrusion cylinder front cover 31, an extrusion cylinder body 32 and an extrusion cylinder rear cover 33. The extrusion cylinder body 32 is fixedly connected between the extrusion cylinder front cover 31 and the extrusion cylinder rear cover 33. A working chamber is formed between the extrusion cylinder front cover 31, the extrusion cylinder body 32 and the extrusion cylinder rear cover 33. A piston is formed at the end of the extrusion rod 3 away from the punch 2. The piston slides with the extrusion cylinder body 32. The piston divides the working chamber into an injection chamber and a return chamber. The extrusion cylinder front cover 31 is fixedly connected to the fixed mold plate 5. A backward flow channel 311 is formed on the extrusion cylinder front cover 31. The backward flow channel 311 is connected to the return chamber. A forward flow channel 331 is formed on the extrusion cylinder rear cover 33. The forward flow channel 331 is connected to the injection chamber. The backward flow channel 311 and the forward flow channel 331 are for hydraulic oil to circulate to drive the extrusion rod 3 to move axially.

[0055] Among them, the front cover 31 of the extrusion cylinder, the extrusion cylinder body 32 and the rear cover 33 of the extrusion cylinder refer to the main body of the hydraulic cylinder composed of a split structure, which can be realized by split casting processing, which is convenient for independent processing and assembly maintenance. The piston refers to a sealing structure integrally formed with the extrusion rod 3, which can be realized by a high-pressure resistant sealing ring in combination with a metal matrix, which is used to isolate the injection cavity and the return cavity and transmit hydraulic thrust. The backward flow channel 311 and the forward flow channel 331 refer to the hydraulic oil channels set on the cylinder head, which can be realized by drilling or casting flow channels, which are used to control the inlet and outlet direction of the hydraulic oil to drive the piston to move.

[0056] Specifically, when the hydraulic oil enters the injection chamber through the forward flow channel 331, the oil pressure pushes the piston to move toward the fixed mold plate 5, and at the same time, the hydraulic oil in the return chamber is discharged through the backward flow channel 311, driving the extrusion rod 3 and the punch 2 to perform the filling action. When the oil is supplied in the reverse direction, the hydraulic oil enters the return chamber to push the piston to reset, and the oil in the injection chamber flows back through the forward flow channel 331 to realize the retraction control of the extrusion rod 3. By independently controlling the flow and pressure of the hydraulic oil in the two chambers, the moving speed and thrust of the extrusion rod 3 can be accurately adjusted.

[0057] Compared with the prior art, the prior art adopts an integral hydraulic cylinder structure, which results in the piston diameter being too large to match the pressure requirement. However, this solution reduces the difficulty of processing through a split cylinder structure, and uses an independent flow channel to achieve bidirectional hydraulic control to avoid pressure overload in a single oil chamber. In addition, the direct connection design between the backward flow channel 311 and the return chamber simplifies the oil circuit layout, which is easier to maintain than the complex oil circuit system of the traditional swing pressure chamber 1.

[0058] Through the above technical solution, this application effectively reduces the machining accuracy requirements and manufacturing costs of the hydraulic cylinder. The split structure can replace the worn parts separately, reducing downtime for maintenance. The setting of independent hydraulic flow channels enables decoupling control of the filling speed and pressurization thrust, avoiding the problem of redundant design of the hydraulic system due to pressurization requirements in traditional solutions, thereby improving the equipment operation stability and process controllability.

[0059] Furthermore, a pressurizing hole is formed on the rear cover 33 of the extrusion cylinder. The pressurizing mechanism includes a pressurizing seat 44, a pressurizing rod 4, and a pressurizing drive assembly. The pressurizing seat 44 is fixedly connected to the rear cover 33 of the extrusion cylinder. The pressurizing rod 4 is slidably connected to the pressurizing seat 44. The pressurizing hole allows the pressurizing rod 4 to extend therein. When the pressurizing rod 4 moves towards the extrusion rod 3, the working cavity is sealed, and the pressurizing rod 4 squeezes the hydraulic oil in the injection cavity to push the extrusion rod 3 to pressurize the molten metal.

[0060] Among them, the pressurizing hole refers to a through-hole structure formed on the rear cover 33 of the extrusion cylinder, which can be specifically realized by a stepped hole or a guide sleeve structure, and is used to guide the pressurizing rod 4 to move axially and form a sealing fit. The pressurizing seat 44 refers to a supporting member rigidly connected to the rear cover 33 of the extrusion cylinder, which can be specifically realized by a flange or an installation base, and is used to provide sliding guidance and a bearing foundation for the pressurizing rod 4. The pressurizing rod 4 refers to a cylindrical power transmission component, which can be specifically realized by a hardened steel rod or a chrome-plated rod body, and changes the pressure of the hydraulic oil in the injection cavity through axial displacement. The pressurizing drive assembly refers to a mechanical power conversion mechanism, which can be specifically realized by a combination of a wedge and a slider or a crank and connecting rod mechanism, and converts the linear motion output by the driving member 43 into the axial displacement of the pressurizing rod 4.

[0061] Specifically, when the filling step is completed, the pressurizing drive assembly starts to act. At this time, the pressurizing rod 4 advances towards the extrusion rod 3 along the guiding surface of the pressurizing seat 44, and its front end passes through the pressurizing hole and enters the working cavity. As the pressurizing rod 4 continues to advance, the hydraulic oil in the injection cavity is compressed, so that the working cavity forms a sealed pressure space. After the pressure of the hydraulic oil increases, the pressure is transmitted to the punch 2 through the extrusion rod 3, thereby applying a continuous holding pressure to the molten metal in the mold cavity. During this process, a dynamic seal is formed between the pressurizing rod 4 and the pressurizing hole through precise cooperation to prevent the leakage of hydraulic oil.

[0062] Compared with the prior art, the traditional solution uses a single hydraulic cylinder to complete both filling and pressurizing at the same time, resulting in an oversized structure size of the hydraulic cylinder and limited control accuracy. In this solution, through the design of a split pressurizing mechanism, the main extrusion cylinder only needs to undertake the rapid propulsion function in the filling stage, while the high-pressure maintenance function is realized by an independent pressurizing component. This division of labor effectively reduces the load intensity of the main hydraulic cylinder, and at the same time allows the pressurizing rod 4 to adopt a small-stroke and high-thrust structure configuration.

[0063] Through the above technical solution, the present application realizes the power separation of the filling and pressurizing processes, avoiding the problem of excessive volume of the hydraulic cylinder caused by the large thrust requirement in traditional equipment. The independent pressurizing mechanism precisely controls the displacement of the pressurizing rod 4 through a mechanical transmission method, enabling the oil pressure in the injection chamber to be stably maintained within the set value range, ensuring that the molten metal continuously bears a uniform pressure during the solidification process. The split structure design also reduces the manufacturing difficulty and maintenance cost of the main hydraulic cylinder, improving the overall reliability of the equipment.

[0064] Further, the pressurizing drive assembly includes a drive member 43, a pressurizing wedge 41, and a wedge block 42. The pressurizing wedge block 42 is slidably connected to the pressurizing seat 44. The pressurizing wedge 41 is formed with a first wedge surface. The wedge block 42 is fixedly connected to the pressurizing rod 4. The wedge block 42 is formed with a second wedge surface. The first wedge surface is in sliding contact with the second wedge surface. The drive member 43 is fixedly connected to the pressurizing seat 44. The drive member 43 is used to drive the pressurizing wedge 41 and the wedge block 42 to slide relative to each other to drive the axial movement of the pressurizing rod 4.

[0065] Among them, the drive member 43 refers to a power source that provides a linear thrust, and specifically can be implemented by a hydraulic cylinder or an electric push rod. Its function is to provide the initial power for the axial movement of the pressurizing rod 4. The pressurizing wedge 41 refers to a transmission component with an inclined sliding surface, and specifically can be processed from a metal block with a trapezoidal cross-section. Its function is to convert the linear motion of the drive member 43 into the axial displacement of the wedge block 42. The wedge block 42 refers to a driven component fixedly connected to the pressurizing rod 4, and specifically can be a steel slider with a matching inclined surface. Its function is to convert the horizontal motion of the wedge into the vertical movement of the pressurizing rod 4 through inclined surface contact. The sliding contact refers to a motion mode in which two components maintain surface contact through mechanical guidance, and specifically can be implemented by a dovetail groove or a linear guide rail structure. Its function is to reduce the motion resistance while transmitting the thrust.

[0066] Specifically, when the drive member 43 pushes the pressurizing wedge 41 to move in the horizontal direction, the first wedge surface and the second wedge surface generate relative sliding. Due to the difference in the inclination angles of the two wedge surfaces, the horizontal displacement of the wedge is converted into the axial displacement of the wedge block 42, thereby driving the pressurizing rod 4 to move along the axis direction of the pressurizing hole. When the pressurizing rod 4 advances towards the pressure chamber 1, the hydraulic oil in the injection chamber is compressed to form a high pressure, and then the extrusion rod 3 is pushed to apply a continuous pressure to the molten metal. The self-locking effect generated by the inclined surface contact during this process can prevent the pressurizing rod 4 from accidentally retracting under the action of high pressure.

[0067] Compared with the prior art, the traditional pressurizing mechanism directly drives the pressure rod 4 with a single hydraulic cylinder, and a large-diameter hydraulic cylinder needs to be configured to meet the high-pressure requirements, resulting in a large equipment volume and high energy consumption. In this solution, the force amplification and direction conversion are achieved through a wedge mechanism, and a driving member 43 with a smaller thrust can be used to produce the same pressurizing effect, effectively reducing the load of the hydraulic system. At the same time, the mechanical cooperation structure of the wedge and the wedge block 42 has higher reliability than a pure hydraulic system, avoiding the pressure loss caused by hydraulic oil leakage.

[0068] Through the above technical solution, the present application realizes the miniaturization and high efficiency of the pressurizing drive mechanism, and solves the problem of structural redundancy caused by the over-large size of a single hydraulic cylinder in traditional equipment. The wedge drive mechanism simplifies the power transmission path while ensuring the pressurizing thrust, reduces the number of kinematic pairs, and improves the operation stability of the equipment. The rigid connection mode between the pressure rod 4 and the wedge block 42 further eliminates the clearance error existing in the traditional link mechanism, ensuring the precise control of the pressurizing process.

[0069] Further, the pressurizing mechanism is provided with a compression spring 45, and the compression spring 45 is used to provide an elastic force for the pressure rod 4 to move away from the pressing chamber 1 side, so that the first wedge surface and the second wedge surface remain in contact.

[0070] Among them, the compression spring 45 is an energy storage element with axial elastic deformation ability, and specifically can be realized by a helical spring or a disc spring, and maintains the contact state between the pressure rod 4 and the wedge through a pre-tightening force. This spring provides a reverse driving force during the reset stage of the pressure rod 4, avoiding the transmission failure caused by the separation of the wedge surfaces.

[0071] Specifically, in the pressurizing step, when the driving member 43 pushes the pressurizing wedge 41 to slide, the relative displacement of the first wedge surface and the second wedge surface causes the pressure rod 4 to move towards the pressing chamber 1 direction, and at this time, the compression spring 45 is compressed to store elastic potential energy. After the pressurizing is completed, the driving member 43 withdraws the pressurizing wedge 41, and the compression spring 45 releases the stored elastic potential energy, pushing the pressure rod 4 to move and reset in the direction away from the pressing chamber 1, while ensuring that the wedge surfaces always remain in contact. This design eliminates the clearance caused by processing errors or wear through the automatic spring-back characteristic of the spring, avoiding the decrease in pressure transmission efficiency caused by hydraulic oil leakage.

[0072] Compared with the prior art, hydraulic locking or mechanical limiting is often used in the traditional pressurizing mechanism to maintain the contact of the wedge surface, which requires an additional control circuit or a complex structure. In this solution, the contact maintenance is realized through the passive elastic action of the compression spring 45, without external power input, simplifies the control system, and reduces the failure risk caused by the failure of hydraulic locking.

[0073] Through the above technical solution, the present application effectively solves the problem of pressure loss caused by unstable contact of the wedge surface during the pressurization process, ensuring reliable transmission of the pressurization thrust to the molten metal. At the same time, the automatic reset function of the spring reduces the need for manual intervention, improves the continuous operation efficiency of the equipment, and reduces the maintenance cost.

[0074] An squeeze casting method, applied to the squeeze casting device casting method of any one of the above, includes the following steps arranged in sequence

[0075] Feeding step: The extrusion assembly and the pressurization assembly are in the initial position, the sealing plate 11 is opened, and the molten metal enters the pressure chamber 1 under the action of air pressure through the feeding runner 12 and the feeding port 102. After reaching the preset injection volume, the sealing plate 11 moves to close the feeding port 102, and the molten metal in the feeding runner 12 flows back into the holding furnace.

[0076] Filling step: The extrusion device pushes the extrusion rod 3 in the direction of the fixed template 5, and the punch 2 pushes the molten metal into the mold cavity until the mold cavity is filled with the molten metal.

[0077] Pressurization step: The extrusion mechanism applies a pressurization thrust to the pressurization rod 4, and transmits the pressurization thrust to the molten metal after filling by increasing the oil pressure in the injection chamber.

[0078] Mold opening step: After cooling, the moving mold 7 moves away from the fixed mold 6, the ejection mechanism in the moving mold 7 ejects the casting from the mold, the pressurization mechanism resets, and the extrusion mechanism continuously pushes the extrusion rod 3 until the punch 2 is exposed outside the fixed mold 6.

[0079] Reset step: The extrusion mechanism drives the extrusion rod 3 and the punch 2 to reset.

[0080] Among them, the air pressure action in the feeding step refers to driving the flow of molten metal by using the gas pressure difference, and specifically can be achieved by means of pressurizing with compressed air or inert gas. This method can avoid exposing the molten metal to the atmospheric environment. The preset injection volume in the filling step refers to the required amount of molten metal calculated according to the volume of the mold cavity, and can be specifically achieved by a liquid level sensor or a weight measuring device to ensure no overflow or shortage of materials during the filling process. The oil pressure transmission in the pressurization step refers to utilizing the incompressible characteristic of the hydraulic system, and can be specifically achieved by a closed injection chamber structure, which can accurately control the static pressure applied to the molten metal. The continuous pushing in the mold opening step refers to the extrusion rod 3 maintaining the advancing state during the ejection stage, and can be specifically achieved by the pressure holding circuit of the hydraulic system to ensure that the punch 2 is completely separated from the formed casting.

[0081] Specifically, after the injection of the molten metal in the pressure chamber 1 is completed during the feeding stage, the sealing plate 11 immediately closes to form a closed space. At this time, the residual molten metal in the feeding runner 12 automatically flows back to the holding furnace under the action of gravity, effectively preventing the remaining material from solidifying and blocking the runner. During the filling stage, the extrusion mechanism precisely controls the advancing speed of the punch 2 through the hydraulic system, enabling the molten metal to smoothly fill the cavity in a laminar flow state, avoiding bubble defects caused by turbulent flow. During the pressurizing stage, the pressurizing mechanism independently set pressurizes the hydraulic oil in the injection chamber, enabling the molten metal during the solidification process to continuously bear a constant pressure, promoting grain refinement and eliminating shrinkage cavities. During the mold opening stage, when the moving mold 7 separates, the extrusion rod 3 advances synchronously to ensure that the punch 2 is completely separated from the casting, avoiding scratches on the casting surface during the ejection process. During the reset stage, each actuator returns to the initial position according to the preset path, preparing for the next production cycle.

[0082] Compared with the prior art, the traditional swing-type pressure chamber 1 needs to tilt and pour the material and then return to the correct position. This method uses a fixed pressure chamber 1 in cooperation with a closed feeding system, reducing the contact time between the molten metal and air, and effectively reducing the defects of oxidation inclusions. In the prior art, a single hydraulic cylinder is shared for filling and pressurizing, resulting in a bulky structure. This method applies pressure during the solidification stage through an independent pressurizing mechanism, not only reducing the load on the main hydraulic cylinder but also improving the pressure holding accuracy. Traditional equipment needs to be started and stopped multiple times to complete each process. This method realizes continuous operation through sequential control, shortening the production cycle of a single piece.

[0083] Through the above technical solutions, this application solves the problems of serious oxidation of molten metal, excessive load on the hydraulic system, and low efficiency of process connection in traditional squeeze casting equipment. The fixed pressure chamber 1 in cooperation with the closed feeding system shortens the exposure time of the molten metal and improves the density of the product. The independent pressurizing mechanism improves the control accuracy of the solidification pressure and guarantees the mechanical properties of the casting. The continuous process flow reduces the no-load time of the equipment and improves the unit production capacity. The modular layout of the actuators reduces the maintenance difficulty and enhances the reliability of the equipment.

[0084] Further, during the filling step, hydraulic oil is injected into the injection chamber through the forward runner 331, and the hydraulic oil is discharged from the return stroke chamber through the backward runner 311, thereby driving the extrusion rod 3 to move in the direction of the fixed template 5. The filling time is controlled by controlling the advancing speed of the extrusion rod 3.

[0085] Among them, the forward flow channel 331 refers to the hydraulic oil channel provided on the rear cover 33 of the extrusion cylinder and communicating with the injection chamber, which can be specifically realized by a pipeline structure with a diameter in the range of 5-50 mm. The amount of oil injected into the injection chamber can be controlled by adjusting the flow parameters of the hydraulic pump. The return chamber refers to the working chamber opposite to the injection chamber separated by the piston of the extrusion rod 3, which is connected to the external hydraulic circuit through the backward flow channel 311, and forms a pressure difference during the filling process to drive the piston to move by draining oil. The forward speed of the extrusion rod 3 refers to the axial displacement rate of the piston under the action of hydraulic thrust, which can be specifically controlled in real time by adjusting the flow parameters or pressure parameters of the hydraulic oil. For example, a proportional valve is used to adjust the flow rate.

[0086] Specifically, during the filling stage, the hydraulic system continuously supplies oil to the injection chamber through the forward flow channel 331, and at the same time, the hydraulic oil in the return chamber is discharged through the backward flow channel 311. The pressure difference formed between the injection chamber and the return chamber drives the piston of the extrusion rod 3 to move towards the fixed mold plate 5, and the punch 2 fixed at the end of the extrusion rod 3 accordingly pushes the molten metal into the mold cavity. By real-time monitoring of the flow and pressure parameters of the hydraulic oil, the moving speed of the extrusion rod 3 can be accurately controlled, so that the filling time is controlled within the range of 0.5-5 seconds, avoiding turbulent gas entrainment of the molten metal caused by too fast speed or premature solidification of the molten metal caused by too slow speed.

[0087] Compared with the prior art, in the traditional filling process, a single hydraulic cylinder is used to achieve both filling and pressurization at the same time. The piston size needs to meet the requirements of both working conditions at the same time, resulting in limited adjustment accuracy of the filling speed. In this solution, by independently controlling the flow of hydraulic oil in the injection chamber and the return chamber, the filling speed and the pressurization thrust are decoupled and controlled, which not only ensures the adjustable speed during the filling stage but also avoids the structural redundancy brought by a large-size hydraulic cylinder.

[0088] Through the above technical solution, the filling time can be dynamically adjusted according to the characteristics of different metal materials and the mold structure. For example, for aluminum alloys with high thermal conductivity, the filling time can be shortened to less than 1 second to prevent local solidification; for thin-walled molds with complex structures, the filling time is appropriately extended to more than 3 seconds to ensure complete filling of the cavity. This precise time control effectively reduces the porosity defects inside the casting and improves the adaptability of the equipment to different working conditions at the same time.

[0089] Further, in the pressurization step, the driving member 43 drives the pressurizing wedge 41 to slide relative to the pressurizing seat 44. The first wedge surface of the pressurizing wedge 41 and the second wedge surface of the wedge block 42 slide relative to each other, driving the pressurizing rod 4 to move axially towards the side close to the pressure chamber 1 along the pressurizing hole, so that the wedge block 42 drives the pressurizing rod 4 to move along the axis of the pressurizing rod 4.

[0090] Among them, the driving member 43 refers to a power source capable of generating a linear motion output, which can be specifically implemented by a hydraulic cylinder or a servo motor. Its function is to provide the driving force required for the movement of the pressing wedge 41. The pressing wedge 41 refers to a rigid member with an inclined contact surface. Its first wedge surface cooperates with the second wedge surface on the wedge block 42, and through sliding contact, converts the linear motion of the driving member 43 into the axial movement of the pressing rod 4, thereby realizing the adjustment of the force transmission direction. The wedge block 42 refers to a component fixedly connected to the pressing rod 4. Its second wedge surface forms a sliding pair with the first wedge surface of the pressing wedge 41, and through inclined surface contact, converts the lateral movement into the longitudinal displacement of the pressing rod 4, thereby realizing the precise control of the hydraulic oil pressure.

[0091] Specifically, during the pressing stage, the driving member 43 pushes the pressing wedge 41 to move in the horizontal direction, and the first wedge surface and the second wedge surface of the wedge block 42 undergo relative sliding. Due to the limitation of the inclination angle of the wedge surface, the wedge block 42 is forced to move toward the side of the pressing chamber 1 along the axial direction of the pressing rod 4 under the constraint of the inclined surface. At this time, the pressing rod 4 extends into the pressing hole of the rear cover 33 of the extrusion cylinder, converting the horizontal movement of the pressing wedge 41 into the longitudinal thrust of the pressing rod 4. This thrust squeezes the hydraulic oil in the injection chamber through the pressing rod 4, causing the oil pressure to rise and be transmitted to the extrusion rod 3, and finally converted into a continuous pressing action on the molten metal at the end of the punch 2. During this process, the angle design of the wedge surface can amplify the output force of the driving member 43, and at the same time, the compression spring 45 provides a reverse elastic force to ensure that the pressing rod 4 quickly resets during the non-pressing stage.

[0092] Compared with the prior art, the traditional device relies on a single hydraulic cylinder to complete both the filling and pressing actions simultaneously, resulting in a complex hydraulic system and an oversized piston size. In this solution, the movement direction of the driving member 43 is converted into the axial movement of the pressing rod 4 through a wedge mechanism, enabling the filling and pressing actions to be performed separately by different mechanisms. This not only simplifies the structure of the hydraulic cylinder but also realizes a force multiplication effect through mechanical wedge surface transmission, reducing the power requirement of the driving member 43. In addition, the rigid contact between the wedge and the wedge block 42 avoids the pressure leakage problem caused by the wear of the sealing parts in the traditional hydraulic system.

[0093] Through the above technical solution, this application realizes the mechanical decoupling of the filling and pressing actions, enabling the pressing thrust to be precisely regulated through the wedge mechanism, effectively avoiding the secondary oxidation of the molten metal during the pressing stage. The rigid contact characteristic of the wedge drive structure reduces the response delay of the hydraulic system, ensuring the timeliness and stability of the pressing action. At the same time, the reset design of the compression spring 45 improves the reliability of the mechanism action and reduces the equipment failure rate.

[0094] Furthermore, a pressing thrust calculation formula is configured in the pressing step, including

[0095]

[0096] Where F represents the magnitude of the pressurizing thrust force, F t represents the thrust force of the driving member, φ1 represents the friction angle between the inclined wedge and the contact surface of the pressurizing seat, φ2 is the friction angle between the first wedge surface and the second wedge surface, and θ is the wedge angle for locking the pressurizing inclined wedge.

[0097] Specifically, the calculation formula for the pressurizing thrust force refers to the mechanical relationship established based on the inclined wedge drive principle. Specifically, it can be derived by using trigonometric functions and friction coefficients to accurately calculate the actual thrust force applied by the pressurizing rod 4. The thrust force of the driving member 43 refers to the original driving force output by the hydraulic cylinder or servo motor. Specifically, it can be achieved by real-time monitoring using a pressure sensor and serves as an input parameter for calculating the pressurizing thrust force. The friction angle between the inclined wedge and the contact surface of the pressurizing seat 44 refers to the angular parameter corresponding to the frictional resistance generated on the contact surface during the transmission process. Specifically, it can be determined by a material friction coefficient test experiment. The friction angle between the first wedge surface and the second wedge surface refers to the friction characteristic parameter between the contact surfaces of the pressurizing inclined wedge 41 and the wedge block 42. Specifically, it can be achieved by using the contact surface roughness control technology. The wedge angle of the locking pressurizing inclined wedge 41 refers to the inclination angle of the working surface of the pressurizing inclined wedge 41. Specifically, it can be precisely machined by a machining process and directly affects the transmission efficiency of the force.

[0098] Specifically, during the execution of the pressurizing step, the thrust force output by the driving member 43 is converted in terms of force value through the inclined wedge mechanism. By establishing a mechanical model that includes frictional losses, the input thrust force of the driving member 43 is converted into the effective output force of the pressurizing rod 4. When performing the pressurizing operation, according to the actually measured friction angle parameters and wedge angle parameters substituted into the calculation formula, the actual pressure value applied to the molten metal is accurately calculated. This calculation process can be corrected in real time in combination with the feedback data of the pressure sensor to ensure that the application accuracy of the pressurizing thrust force is controlled within the allowable error range.

[0099] In some specific embodiments, the measurement of the thrust force of the driving member 43 can be achieved by using a force sensor installed on the piston rod of the hydraulic cylinder. The friction angle of the inclined wedge contact surface can be obtained through a material pairing experiment. For example, when using a friction pair combination of 45# steel and copper alloy, the measured friction angle is 5 - 8 degrees. The wedge angle parameter can be selected according to the design requirements of the equipment structure. For example, standard angle values of 15 degrees or 20 degrees are used. In actual application, the angle parameters in the formula can be pre-stored in the control system and, in combination with a displacement sensor to monitor the stroke position of the pressurizing rod 4, achieve closed-loop control of the pressurizing thrust force.

[0100] Compared with the prior art, the traditional pressurization process lacks an accurate mechanical calculation model and only relies on empirical parameters to set the pressurization pressure, which easily leads to insufficient or excessive pressure. This solution can accurately reflect the force transmission relationship under actual working conditions by establishing a mechanical calculation formula that includes friction loss. Compared with the empirical estimation method, this calculation model can improve the control accuracy of the pressurization thrust by one order of magnitude and avoid the pressure fluctuation problem caused by the estimation deviation of friction loss. This precise control method makes the parameter setting of the pressurization process more scientific and reasonable, effectively solving the problem of casting defects caused by inaccurate pressure control in traditional equipment.

[0101] Through the above technical solution, this application can accurately calculate the actual thrust value during the pressurization process and effectively eliminate the influence of the friction loss of the transmission mechanism on the pressurization effect. This enables the molten metal to obtain a stable and controllable pressurization pressure during the solidification stage, significantly improving the density and mechanical properties of the casting structure. At the same time, the application of the calculation formula simplifies the equipment debugging process. The operator can directly set the drive parameters according to the calculation results, avoiding material waste caused by repeated trial molding. This technical solution fundamentally solves the technical problem of inaccurate pressurization pressure control in traditional equipment and provides a reliable guarantee for the mass production of high-quality extrusion castings.

[0102] Further, the pressure calculation formula for the injection chamber includes:

[0103]

[0104] where p represents the pressure in the injection chamber and D represents the diameter of the pressurization rod.

[0105] Among them, the pressure in the injection chamber refers to the force per unit area formed by the hydraulic oil in the working chamber of the extrusion mechanism, which can be specifically monitored in real time by the pressure sensor of the hydraulic system. This parameter directly affects the pressurization effect of the punch 2 on the molten metal. The magnitude of the pressurization thrust refers to the axial force exerted by the pressurization rod 4 on the hydraulic oil in the injection chamber, which can be specifically obtained by converting the output torque of the servo motor. This parameter determines the solidification pressure finally transmitted to the molten metal. The diameter of the pressurization rod 4 refers to the cross-sectional dimension of the contact part between the pressurization rod 4 and the rear cover 33 of the extrusion cylinder. Specifically, a stepped shaft structure design can be adopted, and this dimensional parameter is positively correlated with the transmission efficiency of the pressurization thrust.

[0106] Specifically, during the execution of the pressurization step, the hydraulic oil in the injection chamber serves as the pressure transmission medium, and its pressure value is determined by the ratio of the axial thrust of the pressurization rod 4 to the cross-sectional area of the pressurization rod 4. By establishing the mathematical relationship between the pressure, the pressurization thrust, and the diameter of the pressurization rod 4, the solidification pressure of the molten metal after filling can be accurately controlled. For example, when the diameter of the pressurization rod 4 is designed to be 80 mm and the pressurization thrust reaches 200 kN, the pressure in the injection chamber can be accurately calculated as 39.79 MPa, providing a theoretical basis for the oil pressure control of the hydraulic system.

[0107] Compared with the prior art, due to the lack of guidance on the pressure calculation formula, traditional equipment generally uses large-sized hydraulic cylinders to ensure pressure margin, resulting in heavy equipment and high energy consumption. By establishing a quantitative relationship between pressure and the parameters of the pressure rod 4, this solution enables the hydraulic system to match the optimal parameter combination according to the actual working conditions. For example, under the same requirement of pressing thrust, the volume of the hydraulic cylinder can be reduced by about 30% by adjusting the diameter of the pressure rod 4.

[0108] Through the above technical solution, this application effectively solves the problem of complex structure caused by the redundant design of the hydraulic system in traditional squeeze casting equipment, realizes the precise matching of the size of the pressure rod 4 and the hydraulic thrust, and significantly reduces the equipment manufacturing cost and maintenance difficulty while ensuring the density of the casting.

[0109] The above is only the preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions falling within the concept of the present invention belong to the protection scope of the present invention. It should be noted that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. An extrusion casting device, characterized in that: including a shot sleeve (1) fixedly connected to a stationary platen (5), a receiving cavity (101) for accommodating molten metal being formed in the shot sleeve (1), a charging port (102) being formed in a side surface of the shot sleeve (1) and connected to a feeding runner (12), a sealing plate (11) being provided at the charging port (102), and the sealing plate (11) being configured to open or close the charging port (102); a punch (2) slidably engaged with the shot sleeve (1); an extrusion mechanism including an extrusion rod (3), the punch (2) being fixedly connected to an end of the extrusion rod (3), and the extrusion mechanism driving the extrusion rod (3) to move based on a hydraulic principle so that the punch (2) pushes the molten metal in the receiving cavity (101) for mold filling; a pressurizing mechanism driving the extrusion rod (3) to move to provide a pressurizing thrust to the molten metal after mold filling.

2. The squeeze casting device according to claim 1, wherein: The extrusion mechanism includes an extrusion cylinder front cover (31), an extrusion cylinder body (32), and an extrusion cylinder rear cover (33). The extrusion cylinder body (32) is fixedly connected between the extrusion cylinder front cover (31) and the extrusion cylinder rear cover (33). A working chamber is formed among the extrusion cylinder front cover (31), the extrusion cylinder body (32), and the extrusion cylinder rear cover (33). A piston is formed at an end of the extrusion rod (3) away from the punch (2). The piston is slidably engaged with the extrusion cylinder body (32). The piston divides the working chamber into a shot chamber and a return chamber. The extrusion cylinder front cover (31) is fixedly connected to the stationary platen (5). A return runner (311) is formed on the extrusion cylinder front cover (31), and the return runner (311) is communicated with the return chamber. A forward runner (331) is formed on the extrusion cylinder rear cover (33), and the forward runner (331) is communicated with the shot chamber. The return runner (311) and the forward runner (331) are for hydraulic oil to flow through to drive the extrusion rod (3) to move axially.

3. The squeeze casting device according to claim 2, wherein: A pressurizing hole is formed in the extrusion cylinder rear cover (33). The pressurizing mechanism includes a pressurizing seat (44), a pressurizing rod (4), and a pressurizing driving assembly. The pressurizing seat (44) is fixedly connected to the extrusion cylinder rear cover (33). The pressurizing rod (4) is slidably connected to the pressurizing seat (44). The pressurizing hole is for the pressurizing rod (4) to extend into. When the pressurizing rod (4) moves in a direction close to the extrusion rod (3), the working chamber is sealed, and the pressurizing rod (4) extrudes the hydraulic oil in the shot chamber to push the extrusion rod (3) to pressurize the molten metal.

4. The squeeze casting device according to claim 3, characterized in that: The pressurizing driving assembly includes a driving member, a pressurizing wedge (41), and a wedge block (42). The pressurizing wedge block (42) is slidably connected to the pressurizing seat (44). A first wedge surface is formed on the pressurizing wedge (41). The wedge block (42) and the pressurizing rod (4) are fixedly connected. A second wedge surface is formed on the wedge block (42). The first wedge surface is in sliding contact with the second wedge surface. The driving member is fixedly connected to the pressurizing seat (44). The driving member is configured to drive the pressurizing wedge (41) and the wedge block (42) to slide relative to each other to drive the pressurizing rod (4) to move axially.

5. The squeeze casting device according to claim 4, wherein: The pressurizing mechanism is provided with a compression spring (45), and the compression spring (45) is used to provide an elastic force for the pressurizing rod (4) to move away from the pressure chamber (1) so that the first wedge surface and the second wedge surface remain in contact.

6. A squeeze casting method, applied to the squeeze casting device described in any one of claims 1-5, characterized in that: The casting method includes the following steps arranged in sequence Feeding step: The extrusion assembly and the pressurizing assembly are in the initial position, the sealing plate (11) is opened, and the molten metal enters the pressure chamber (1) under the action of air pressure through the feeding runner (12) and the feeding port (102). After reaching the preset injection volume, the sealing plate (11) moves to close the feeding port (102), and the molten metal in the feeding runner (12) flows back into the holding furnace. Filling step: The extrusion device pushes the extrusion rod (3) towards the fixed template (5). The punch (2) pushes the molten metal into the mold cavity until the mold cavity is filled with the molten metal. Pressurizing step: The extrusion mechanism applies a pressurizing thrust to the pressurizing rod (4), and transfers the pressurizing thrust to the molten metal after filling by increasing the oil pressure in the injection chamber. Mold opening step: After cooling, the moving mold (7) moves away from the fixed mold (6). The ejection mechanism in the moving mold (7) ejects the casting from the mold. The pressurizing mechanism resets, and the extrusion mechanism continuously pushes the extrusion rod (3) until the punch (2) is exposed outside the fixed mold (6). Reset step: The extrusion mechanism drives the extrusion rod (3) and the punch (2) to reset.

7. The squeeze casting method according to claim 6, characterized in that: In the filling step, hydraulic oil is injected into the injection chamber through the forward runner (331), and the hydraulic oil is discharged from the return chamber through the backward runner (311), thereby pushing the extrusion rod (3) towards the fixed template (5). The filling time is controlled by controlling the forward speed of the extrusion rod.

8. The squeeze casting method according to claim 6, characterized in that: In the pressurizing step, the driving member drives the pressurizing wedge (41) to slide relative to the pressurizing seat (44). The first wedge surface of the pressurizing wedge (41) slides relative to the second wedge surface of the wedge block (42), driving the pressurizing rod (4) to move towards the pressure chamber (1) along the axis of the pressurizing hole, so that the wedge block (42) drives the pressurizing rod (4) to move along the axis of the pressurizing rod (4).

9. The squeeze casting method according to claim 6, wherein: In the pressurizing step, a pressurizing thrust calculation formula is configured, including Among them, F represents the magnitude of the pressurizing thrust, F t represents the thrust of the driving part, φ1 represents the friction angle between the contact surfaces of the inclined wedge and the pressurizing seat, φ2 is the friction angle between the first wedge surface and the second wedge surface, and θ is the wedge angle for locking the pressurizing inclined wedge.

10. The squeeze casting method according to claim 6, characterized in that: The pressure calculation formula of the injection chamber includes: Where p represents the pressure in the injection chamber, and D represents the diameter of the pressurizing rod.

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