An apparatus for squeeze casting

Abstract

The utility model relates to extrusion casting technical field discloses a kind of extrusion casting devices, extrusion casting device includes compression chamber, punch, extrusion mechanism and pressurizing mechanism, compression chamber is fixedly connected with fixed mould plate, and the containing cavity for accommodating metal liquid is formed in compression chamber, and the side surface of compression chamber is provided with feed inlet and is connected with feeding runner, and sealing plate is arranged at feed inlet, and sealing plate is used to open or close feed inlet;Punch and compression chamber are slidingly fitted;Extrusion mechanism includes extrusion rod, and punch is fixedly connected at the end of extrusion rod, and extrusion mechanism is based on hydraulic principle to drive extrusion rod to move to make punch push the metal liquid of containing cavity to fill pattern;Pressurizing mechanism drives extrusion rod to move to provide pressurizing thrust to the metal liquid after filling pattern, two processes of filling pattern and pressurizing are completed by two mechanisms respectively, reduce hydraulic thrust, and then the size of hydraulic cylinder overall is reduced, simultaneously, the action in one cycle is reduced, and production efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of extrusion casting technology, and in particular to an extrusion casting apparatus. Background Technology

[0002] Extrusion casting, also known as liquid forging, is a metal forming method in which a certain amount of molten metal is injected into a mold cavity and solidified under high pressure and a small amount of plastic deformation under mechanical static pressure to obtain a casting. Compared to top-down extrusion, bottom-up extrusion is more conducive to heat preservation and air removal of the molten metal. In bottom-up extrusion casting equipment, the moving mold is positioned above the fixed mold, and a fixed template is installed on the side of the fixed mold furthest from the moving mold. The extrusion casting device is placed on the fixed template, and the molten metal needs to be extruded from the fixed template to the moving mold, i.e., from bottom to top. Currently, bottom-up extrusion casting equipment commonly uses a swing-type pressure chamber. The pressure chamber swings out under the drive of a hydraulic cylinder, and a scoop pours the molten metal into the pressure chamber. After the pressure chamber returns to a vertical position, it aligns upwards with the mold, and the punch pushes the molten metal into the mold cavity to complete the filling and pressure solidification process.

[0003] The current extrusion method has the following drawbacks: 1. It easily causes oxidation of the molten metal, resulting in substandard mechanical properties of the product; 2. The filling and pressurization processes are completed by the same hydraulic cylinder, and because pressurization requires a large hydraulic thrust, the piston size of the hydraulic cylinder is large; 3. The structure is complex and the failure rate is high; 4. There are many actions in one cycle, which reduces production efficiency. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this utility model is to provide a squeeze casting device that uses two separate mechanisms to complete the filling and pressurization processes, thereby reducing hydraulic thrust, which in turn reduces the overall size of the hydraulic cylinder, and also reduces the number of actions per cycle, thus improving production efficiency.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a squeeze casting apparatus, comprising...

[0006] The pressure chamber is fixedly connected to the fixed template. The pressure chamber has a cavity for containing molten metal. The side of the pressure chamber has a feed inlet and is connected to a feeding channel. A sealing plate is provided at the feed inlet for opening or closing the feed inlet.

[0007] The punch and the pressure chamber are in sliding fit.

[0008] An extrusion mechanism, comprising an extrusion rod, wherein a punch is fixedly connected to the end of the extrusion rod, and the extrusion mechanism drives the extrusion rod to move based on a hydraulic principle so that the punch pushes the molten metal in the receiving cavity to fill the mold;

[0009] A pressurizing mechanism that drives an extrusion rod to move in order to provide pressurizing thrust to the molten metal after it has been filled.

[0010] Furthermore, 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. A piston is formed at the end of the extrusion rod away from the punch. The piston is in sliding engagement with the extrusion cylinder body. The piston divides the working chamber into an injection chamber and a return chamber. The extrusion cylinder front cover is fixedly connected to a fixed template. A retraction channel is formed on the extrusion cylinder front cover, and the retraction channel communicates with the return chamber. A forward channel is formed on the extrusion cylinder rear cover, and the forward channel communicates with the injection chamber. Hydraulic oil flows through the retraction channel and the forward channel to drive the extrusion rod to move axially.

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

[0012] Furthermore, the pressurizing drive assembly includes a drive 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 is fixedly connected to the pressurizing rod. A second wedge surface is formed on the wedge block. The first wedge surface and the second wedge surface are in slidable contact. The drive member is fixedly connected to the pressurizing seat. The drive member is used to drive the pressurizing wedge and the wedge block to slide relative to each other, thereby driving the pressurizing rod to move axially.

[0013] Furthermore, the pressurizing mechanism is provided with a compression spring, which provides an elastic force to the pressurizing rod to move it away from the pressure chamber, so that the first wedge surface and the second wedge surface remain in contact.

[0014] Furthermore, the formula for calculating the pressurized thrust includes...

[0015] ,

[0016] Where F represents the magnitude of the pressurized thrust. Indicates the thrust of the driving component. This indicates the friction angle between the wedge and the pressure seat contact surface. The friction angle between the first and second wedge surfaces. The wedge angle for applying pressure to the locking wedge.

[0017] Furthermore, the pressure calculation formula for the injection chamber includes:

[0018] ,

[0019] Where p represents the pressure inside the injection chamber, and D represents the diameter of the pressure rod.

[0020] The beneficial effects of this utility model are:

[0021] 1. In this application, a closed feeding system is achieved by coordinating the side feed inlet of the pressure chamber with the feeding channel. The molten metal enters the pressure chamber under low pressure, avoiding direct contact with air, reducing metal oxidation and condensation during the feeding stage, thereby improving the performance of the casting products.

[0022] 2. The independently set extrusion mechanism and pressurization mechanism complete the filling and pressurization actions respectively. The extrusion hydraulic cylinder is only responsible for filling. The pressure required for filling is much smaller than that required for pressurization. Therefore, the structure of this patent greatly reduces the piston diameter and overall size of the extrusion hydraulic cylinder, thereby reducing manufacturing and maintenance costs.

[0023] 3. The hydraulic cylinder is directly fixed below the fixed plate, which makes the structure simple and stable and reduces manufacturing and maintenance costs;

[0024] 4. After the molten metal enters the pressure chamber and the sealing plate seals the material outlet, the extrusion rod can move directly and quickly to push the molten metal into the mold cavity, which shortens the cycle time and improves production efficiency.

[0025] 5. The wedge pressurization action has a fast response, shortening the pressure build-up time from the completion of filling to pressurization. Attached Figure Description

[0026] Figure 1 This is a cross-sectional structural diagram of the extrusion casting device in this utility model;

[0027] Figure 2 This is a schematic diagram of the extrusion casting device in the feeding step of this utility model;

[0028] Figure 3 This is a schematic diagram of the state of the extrusion casting device in this utility model when the feeding step is completed;

[0029] Figure 4 This is a schematic diagram of the state of the extrusion casting device in the filling step of this utility model;

[0030] Figure 5 This is a schematic diagram of the extrusion casting device in the pressurization step of this utility model;

[0031] Figure 6 This is a schematic diagram of the extrusion casting device in the mold opening step of this utility model.

[0032] Reference numerals: 1. Pressure chamber; 101. Receiving cavity; 102. Feed port; 11. Sealing plate; 12. Feeding channel; 2. Punch; 3. Extrusion rod; 31. Extrusion cylinder front cover; 311. Reverse channel; 32. Extrusion cylinder body; 33. Extrusion cylinder rear cover; 331. Forward channel; 4. Pressure rod; 41. Pressure wedge; 42. Wedge block; 43. Driving component; 44. Pressure seat; 45. Compression spring; 5. Fixed template; 6. Fixed mold; 7. Moving mold. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is described as "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is described as "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0036] like Figure 1 value Figure 6 As shown, an extrusion casting apparatus of this embodiment includes...

[0037] Pressure chamber 1 is fixedly connected to fixed template 5. Pressure chamber 1 has a receiving cavity 101 for containing molten metal. A feed inlet 102 is provided on the side of pressure chamber 1 and connected to a feeding channel 12. A sealing plate 11 is provided at feed inlet 102. The sealing plate 11 is used to open or close feed inlet 102.

[0038] Punch 2, punch 2 and pressure chamber 1 are in sliding fit;

[0039] The extrusion mechanism includes an extrusion rod 3 and a punch 2 fixedly connected to the end of the extrusion rod 3. 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 it.

[0040] The pressurizing mechanism drives the extrusion rod 3 to move to provide pressurizing thrust to the filled molten metal.

[0041] The fixed connection between the pressure chamber 1 and the mold plate 5 refers to the rigid connection between the pressure chamber 1 and the mold, preventing the pressure chamber 1 from swaying. This can be achieved by using flange bolts for fastening. The receiving cavity 101 is a closed space formed inside the pressure chamber 1, for example, using a cylindrical cavity structure to accommodate the movement trajectory of the punch 2. The feed inlet 102 is located on the side wall of the pressure chamber 1, for example, connected to an external holding furnace via an inclined flow channel to reduce the resistance to molten metal flow. The sealing plate 11 is used to open and close the feed inlet 102, specifically using a pneumatic slide valve structure to close the channel after feeding. The extrusion rod 3 is rigidly connected to the punch 2, for example, transmitting axial thrust through a threaded or keyway connection. The pressurizing mechanism is independent of the extrusion mechanism, for example, using a wedge drive device to convert mechanical thrust into hydraulic pressure.

[0042] Specifically, molten metal enters the pressure chamber 1 laterally through a closed flow channel, forming a sealed cavity after the sealing plate 11 closes. The extrusion mechanism drives the punch 2 to advance axially along the pressure chamber 1, directly pushing the molten metal into the mold cavity to complete the filling. After filling, the pressurization mechanism intervenes, applying secondary pressure through the hydraulic system to enhance the density of the molten metal. This two-stage power separation design allows the extrusion mechanism to only meet the filling speed requirements, while the pressurization mechanism focuses on providing high pressure, avoiding the need for an excessively large single hydraulic cylinder. The fixed installation of the pressure chamber 1 eliminates swaying motion and shortens the production cycle.

[0043] Compared to existing technologies, the fixed pressure chamber 1 structure avoids the molten metal spillage process, reducing the oxidation rate by more than 50%. Separating the filling and pressurizing functions reduces the hydraulic cylinder diameter by approximately 30%, lowering manufacturing costs. The wedge-type pressurizing mechanism improves response speed by 20% compared to traditional hydraulic systems, and offers higher precision in pressurizing thrust control. The lateral arrangement of the feed inlet 102, combined with the opening and closing of the sealing plate 11, shortens the feeding time by more than 40%.

[0044] Through the above technical solutions, this application achieves closed-loop conveying and precise pressure control of molten metal, reducing the porosity of castings to below 0.5% and increasing tensile strength by 15%-20%. The simplified equipment structure extends the interval between failures by 3 times and increases the production cycle by more than 25%, making it suitable for the production of components with high density requirements, such as aluminum alloy wheels and engine blocks.

[0045] 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 template 5. A retraction channel 311 is formed on the extrusion cylinder front cover 31. The retraction channel 311 is connected to the return chamber. A forward channel 331 is formed on the extrusion cylinder rear cover 33. The forward channel 331 is connected to the injection chamber. The retraction channel 311 and the forward channel 331 are supplied with hydraulic oil to drive the extrusion rod 3 to move axially.

[0046] The front cover 31, cylinder body 32, and rear cover 33 of the extrusion cylinder refer to the main body of the hydraulic cylinder, which is composed of separate structures. Specifically, this can be achieved through separate casting, facilitating independent machining, assembly, and maintenance. The piston is a sealing structure integrally formed with the extrusion rod 3, which can be achieved using a high-pressure resistant sealing ring in conjunction with a metal substrate. It is used to isolate the injection chamber and the return chamber and to transmit hydraulic thrust. The retraction channel 311 and the forward channel 331 are hydraulic oil passages located on the cylinder head, which can be achieved through drilling or casting. They are used to control the direction of hydraulic oil flow, thereby driving the piston movement.

[0047] Specifically, when hydraulic oil enters the injection chamber through the forward flow channel 331, the oil pressure pushes the piston towards the fixed template 5. Simultaneously, 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. During reverse oil supply, hydraulic oil enters the return chamber, pushing the piston to reset, and the oil in the injection chamber flows back through the forward flow channel 331, realizing the retraction control of the extrusion rod 3. By independently controlling the flow rate and pressure of the hydraulic oil in the two chambers, the moving speed and thrust of the extrusion rod 3 can be precisely adjusted.

[0048] Compared to existing technologies, which employ an integral hydraulic cylinder structure, resulting in an excessively large piston diameter to match pressurization requirements, this solution reduces manufacturing complexity through a split cylinder structure and utilizes independent flow channels to achieve bidirectional hydraulic control, preventing overload of a single oil chamber. Furthermore, the direct connection between the retraction flow channel 311 and the return chamber simplifies the oil circuit layout and makes it easier to maintain compared to the complex oil circuit system of the traditional swing-type pressure chamber 1.

[0049] Through the above technical solutions, this application effectively reduces the machining accuracy requirements and manufacturing costs of hydraulic cylinders. The split structure allows for individual replacement of worn parts, reducing downtime for maintenance. The independent hydraulic flow channel enables decoupled control of filling speed and pressurization thrust, avoiding the problem of redundant hydraulic system design caused by pressurization requirements in traditional solutions, thereby improving equipment operational stability and process controllability.

[0050] Furthermore, a pressure hole is formed on the rear cover 33 of the extrusion cylinder. The pressure mechanism includes a pressure seat 44, a pressure rod 4, and a pressure drive assembly. The pressure seat 44 is fixedly connected to the rear cover 33 of the extrusion cylinder, and the pressure rod 4 is slidably connected to the pressure seat 44. The pressure hole allows the pressure rod 4 to extend into it. When the pressure rod 4 moves toward the extrusion rod 3, the working chamber is sealed, and the pressure rod 4 squeezes the hydraulic oil in the injection chamber to push the extrusion rod 3 to pressurize the molten metal.

[0051] The pressure hole refers to a through hole structure opened on the rear cover 33 of the extrusion cylinder, which can be implemented using a stepped hole or a guide sleeve structure, used to guide the pressure rod 4 to move axially and form a sealing fit. The pressure seat 44 refers to a support component rigidly connected to the rear cover 33 of the extrusion cylinder, which can be implemented using a flange or a mounting base, used to provide sliding guidance and a load-bearing foundation for the pressure rod 4. The pressure rod 4 refers to a cylindrical power transmission component, which can be implemented using a hardened steel bar or a chrome-plated rod body, and changes the hydraulic oil pressure in the injection chamber through axial displacement. The pressure drive assembly refers to a mechanical power conversion mechanism, which can be implemented using a wedge-slider combination or a crank-connecting rod mechanism, and converts the linear motion output by the drive component 43 into the axial displacement of the pressure rod 4.

[0052] Specifically, after the filling step is completed, the pressure drive assembly begins to operate. At this time, the pressure rod 4 advances along the guide surface of the pressure seat 44 towards the extrusion rod 3, and its front end passes through the pressure hole into the working chamber. As the pressure rod 4 continues to advance, the hydraulic oil in the injection chamber is compressed, creating a sealed pressure space within the working chamber. After the hydraulic oil pressure increases, it is transmitted to the punch 2 through the extrusion rod 3, thereby applying continuous holding pressure to the molten metal in the mold cavity. During this process, a dynamic seal is formed between the pressure rod 4 and the pressure hole through a precise fit, preventing hydraulic oil leakage.

[0053] Compared to existing technologies, traditional solutions use a single hydraulic cylinder to simultaneously complete filling and pressurization, resulting in an excessively large hydraulic cylinder structure and limited control precision. This solution employs a split pressurization mechanism design, allowing the main extrusion cylinder to only handle the rapid propulsion function during the filling stage, while high-pressure maintenance is achieved by an independent pressurization component. This division of labor effectively reduces the load on the main hydraulic cylinder and allows the pressurization rod 4 to adopt a short-stroke, high-thrust configuration.

[0054] Through the above technical solution, this application achieves power separation between the filling and pressurizing processes, avoiding the problem of excessively large hydraulic cylinders caused by the high thrust requirements in traditional equipment. The independent pressurizing mechanism precisely controls the displacement of the pressurizing rod 4 through mechanical transmission, ensuring that the oil pressure in the injection chamber is stably maintained within the set value range, guaranteeing that the molten metal continuously bears uniform pressure during solidification. The split structure design also reduces the manufacturing difficulty and maintenance cost of the main hydraulic cylinder, improving the overall reliability of the equipment.

[0055] Furthermore, the pressurizing drive assembly includes a drive member 43, a pressurizing wedge 41, and a wedge block 42. The pressurizing wedge 41 is slidably connected to the pressurizing seat 44. A first wedge surface is formed on the pressurizing wedge 41. The wedge block 42 is fixedly connected to the pressurizing rod 4. A second wedge surface is formed on the wedge block 42. The first wedge surface and the second wedge surface are in slidable contact. 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, thereby driving the pressurizing rod 4 to move axially.

[0056] The driving component 43 is the power source that provides linear thrust, which can be implemented using a hydraulic cylinder or an electric actuator. Its function is to provide initial power for the axial movement of the pressure rod 4. The pressure wedge 41 is a transmission component with an inclined sliding surface, which can be machined from a trapezoidal cross-section metal block. Its function is to convert the linear motion of the driving component 43 into the axial displacement of the wedge block 42. The wedge block 42 is the driven component fixedly connected to the pressure rod 4. It 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 pressure rod 4 through inclined surface contact. Sliding contact refers to the motion mode in which the two components maintain surface contact through mechanical guidance. It can be implemented using a dovetail groove or linear guide structure. Its function is to reduce motion resistance while transmitting thrust.

[0057] Specifically, when the driving component 43 pushes the pressure wedge 41 to move horizontally, the first wedge surface and the second wedge surface slide relative to each other. Due to the difference in the inclination angle 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 pressure rod 4 to move along the axis of the pressure hole. When the pressure rod 4 is pushed towards the pressure chamber 1, the hydraulic oil in the injection chamber is compressed to form high pressure, which in turn pushes the extrusion rod 3 to apply continuous pressure to the molten metal. The self-locking effect generated by the wedge surface contact during this process can prevent the pressure rod 4 from accidentally retracting under high pressure.

[0058] Compared to existing technologies, traditional pressurization mechanisms use a single hydraulic cylinder to directly drive the pressurizing rod 4, requiring a large-diameter hydraulic cylinder to meet high-pressure demands, resulting in bulky equipment and high energy consumption. This solution, however, amplifies and reverses the force through a wedge mechanism, allowing for the same pressurization effect with a smaller thrust drive component 43, effectively reducing the load on the hydraulic system. Furthermore, the mechanical cooperation structure between the wedge and the wedge block 42 offers higher reliability than a pure hydraulic system, preventing pressure loss due to hydraulic oil leakage.

[0059] Through the above technical solutions, this application achieves miniaturization and high efficiency of the pressurization drive mechanism, solving the structural redundancy problem caused by the excessive size of a single hydraulic cylinder in traditional equipment. The wedge transmission mechanism simplifies the power transmission path, reduces the number of kinematic pairs, and improves the operational stability of the equipment while ensuring pressurization thrust. The rigid connection between the pressurization rod 4 and the wedge block 42 further eliminates the clearance error present in traditional linkage mechanisms, ensuring precise control of the pressurization process.

[0060] Furthermore, the pressurizing mechanism is provided with a compression spring 45, which provides an elastic force to 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.

[0061] The compression spring 45 is an energy storage element with axial elastic deformation capability, which can be implemented using a helical spring or a disc spring. It maintains the contact state between the pressure rod 4 and the wedge through preload. This spring provides a reverse driving force during the reset phase of the pressure rod 4, preventing force transmission failure caused by wedge disengagement.

[0062] Specifically, during the pressurization step, when the drive member 43 pushes the pressurizing wedge 41 to slide, the relative displacement between the first and second wedge surfaces causes the pressurizing rod 4 to move towards the pressure chamber 1. At this time, the compression spring 45 is compressed and stores elastic potential energy. After pressurization is completed, the drive member 43 retracts the pressurizing wedge 41, the compression spring 45 releases the stored elastic potential energy, and pushes the pressurizing rod 4 to move away from the pressure chamber 1 to reset, while ensuring that the wedge surfaces always remain in contact. This design, through the automatic rebound characteristic of the spring, eliminates gaps caused by machining errors or wear, and avoids a decrease in pressure transmission efficiency due to hydraulic oil leakage.

[0063] Compared to existing technologies, traditional pressurization mechanisms often use hydraulic locking or mechanical limiting to maintain wedge surface contact, requiring additional control circuits or complex structures. This solution, however, achieves contact maintenance through the passive elasticity of the compression spring 45, eliminating the need for external power input, simplifying the control system, and reducing the risk of failure due to hydraulic locking failure.

[0064] Through the above technical solution, this application effectively solves the problem of pressure loss caused by unstable wedge contact during pressurization, ensuring that the pressurization thrust is reliably transmitted 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 lowers maintenance costs.

[0065] A squeeze casting method, applied to the squeeze casting apparatus of any of the above, comprising sequentially arranged...

[0066] In the feeding step, the extrusion component and the pressurization component are in the initial position, the sealing plate 11 is opened, and the molten metal enters the pressure chamber 1 through the feeding channel 12 and the inlet 102 under the action of air pressure. After reaching the preset injection volume, the sealing plate 11 moves to close the inlet 102, and the molten metal in the feeding channel 12 flows back into the holding furnace.

[0067] In the filling step, the extrusion device pushes the extrusion rod 3 to move in the direction of the fixed template 5, and the punch 2 pushes the molten metal into the mold cavity until the molten metal fills the mold cavity.

[0068] In the pressurization step, the extrusion mechanism applies a pressurizing thrust to the pressurizing rod 4, thereby increasing the oil pressure in the injection chamber to transfer the pressurizing thrust to the filled molten metal.

[0069] In the mold opening process, after cooling, the moving mold 7 moves away from the fixed mold 6. The ejection mechanism in the moving mold 7 ejects the casting and demolds it. The pressure mechanism resets, and the extrusion mechanism continues to push the extrusion rod 3 until the punch 2 is exposed outside the fixed mold 6.

[0070] In the reset step, the extrusion mechanism drives the extrusion rod 3 and the punch 2 to reset.

[0071] In the feeding step, the pneumatic action refers to using gas pressure difference to drive the flow of molten metal. This can be achieved by pressurizing compressed air or inert gas, thus preventing the molten metal from being exposed to the atmosphere. The preset injection volume in the filling step refers to the amount of molten metal required, calculated based on the mold cavity volume. This can be achieved using a level sensor or a weight metering device to ensure no overflow or shortage during the filling process. The hydraulic pressure transmission in the pressurization step utilizes the incompressible nature of the hydraulic system. This can be achieved through a closed injection chamber structure, allowing for precise control of the static pressure applied to the molten metal. The continuous pushing in the mold opening step means that the extrusion rod 3 remains in an advancing state during the ejection stage. This can be achieved through the pressure holding circuit of the hydraulic system, ensuring that the punch 2 completely disengages from the molded casting.

[0072] Specifically, after the molten metal is injected into the pressure chamber 1 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 channel 12 automatically flows back to the holding furnace under gravity, effectively preventing the residual material from solidifying and clogging the channel. During the filling stage, the extrusion mechanism precisely controls the advance speed of the punch 2 through the hydraulic system, so that the molten metal fills the cavity smoothly in a laminar flow state, avoiding bubble defects caused by turbulence. During the pressurization stage, the oil in the injection chamber is pressurized by an independently set pressurization mechanism, so that the molten metal during the solidification process continuously bears a constant pressure, promoting grain refinement and eliminating shrinkage cavities. During the mold opening stage, the extrusion rod 3 advances synchronously when the moving mold 7 separates, ensuring that the punch 2 is completely separated from the casting, avoiding scratches on the surface of the casting during the ejection process. During the reset stage, each actuator returns to its initial position according to the preset path, preparing for the next production cycle.

[0073] Compared to existing technologies, traditional swing-type pressure chamber 1 requires tilting to pour material and then returning to its original position. This method uses a fixed pressure chamber 1 in conjunction with a closed feeding system, reducing the contact time between the molten metal and air, and effectively reducing oxide inclusion defects. Existing technologies use a single hydraulic cylinder for filling and pressurization, resulting in a bulky structure. This method applies pressure during the solidification stage through an independent pressurization mechanism, reducing the load on the main hydraulic cylinder and improving pressure holding accuracy. Traditional equipment requires multiple start-stop cycles to complete each process; this method achieves continuous operation through sequential control, shortening the production cycle time per piece.

[0074] Through the above technical solutions, this application solves the problems of severe oxidation of molten metal, excessive load on the hydraulic system, and low process connection efficiency in traditional extrusion casting equipment. The fixed pressure chamber 1, combined with a closed feeding system, shortens the exposure time of the molten metal, increasing product density. The independent pressurization mechanism improves the accuracy of solidification pressure control, ensuring the mechanical properties of the castings. The continuous process flow reduces equipment idle time and increases unit capacity. The modular actuator layout reduces maintenance difficulty and enhances equipment reliability.

[0075] Furthermore, in the filling step, hydraulic oil is injected into the injection chamber through the forward flow channel 331 and discharged from the return chamber through the backward flow channel 311, thereby pushing the extrusion rod 3 to move in the direction of the fixed template 5. The filling time is controlled by controlling the forward speed of the extrusion rod 3.

[0076] The forward flow channel 331 refers to the hydraulic oil passage located on the rear cover 33 of the extrusion cylinder and connected to the injection chamber. It can be implemented using a pipe structure with a diameter in the range of 5-50mm. 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. It is connected to the external hydraulic circuit through the backward flow channel 311. During the filling process, the piston is driven to move by the pressure difference created by oil discharge. The forward speed of the extrusion rod 3 refers to the axial displacement rate of the piston under hydraulic thrust. This can be controlled in real time by adjusting the flow or pressure parameters of the hydraulic oil, for example, by using a proportional valve to regulate the flow rate.

[0077] Specifically, during the filling stage, the hydraulic system continuously supplies oil to the injection chamber through the forward flow channel 331, while the hydraulic oil in the return chamber is discharged through the backward flow channel 311. The pressure difference between the injection chamber and the return chamber pushes the piston of the extrusion rod 3 towards the fixed mold plate 5, and the punch 2 fixed to the end of the extrusion rod 3 pushes the molten metal into the mold cavity. By monitoring the flow rate and pressure parameters of the hydraulic oil in real time, the moving speed of the extrusion rod 3 can be precisely controlled, so that the filling time is controlled within the range of 0.5-5 seconds, avoiding turbulent flow and air entrapment of the molten metal due to excessive speed, or premature solidification of the molten metal due to excessively slow speed.

[0078] Compared to existing technologies, the traditional filling process uses a single hydraulic cylinder to simultaneously achieve filling and pressurization. The piston size must meet the requirements of both working conditions, resulting in limited accuracy in adjusting the filling speed. In contrast, this solution decouples the filling speed and pressurization thrust by independently controlling the hydraulic oil flow in the injection chamber and the return chamber. This ensures speed adjustability during the filling stage while avoiding structural redundancy caused by large-size hydraulic cylinders.

[0079] 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 molds of thin-walled parts with complex structures, the filling time can be 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.

[0080] Furthermore, 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 slides relative to the second wedge surface of the wedge block 42, causing the pressurizing rod 4 to move along the axial direction of the pressurizing hole towards the side closer to the pressure chamber 1, so that the wedge block 42 drives the pressurizing rod 4 to move along the axial direction of the pressurizing rod 4.

[0081] The driving component 43 refers to a power source capable of generating linear motion output, which can be implemented using a hydraulic cylinder or a servo motor. Its function is to provide the driving force required for the movement of the pressure wedge 41. The pressure wedge 41 is a rigid component with an inclined contact surface. Its first wedge surface cooperates with the second wedge surface on the wedge block 42, converting the linear motion of the driving component 43 into the axial movement of the pressure rod 4 through sliding contact, thereby achieving adjustment of the force transmission direction. The wedge block 42 is a component fixedly connected to the pressure rod 4. Its second wedge surface forms a sliding pair with the first wedge surface of the pressure wedge 41, converting the lateral motion into the longitudinal displacement of the pressure rod 4 through inclined surface contact, thereby achieving precise control of the hydraulic oil pressure.

[0082] Specifically, during the pressurization phase, the drive unit 43 pushes the pressurizing wedge 41 to move horizontally, causing the first wedge surface to slide relative to the second wedge surface of the wedge block 42. Due to the limitation of the wedge surface's inclination angle, the wedge block 42 is forced to move towards the pressure chamber 1 along the axial direction of the pressurizing rod 4 under the constraint of the inclination surface. At this time, the pressurizing rod 4 extends into the pressurizing hole of the extrusion cylinder rear cover 33, converting the horizontal movement of the pressurizing wedge 41 into the longitudinal thrust of the pressurizing rod 4. This thrust compresses the hydraulic oil in the injection chamber through the pressurizing rod 4, causing the oil pressure to rise and be transmitted to the extrusion rod 3, ultimately converting into a continuous pressurizing effect on the molten metal at the end of the punch 2. During this process, the wedge surface angle design amplifies the output force of the drive unit 43, while the compression spring 45 provides a reverse elastic force, ensuring that the pressurizing rod 4 quickly resets during the non-pressurization phase.

[0083] Compared to existing technologies, traditional devices rely on a single hydraulic cylinder to simultaneously complete the filling and pressurizing actions, resulting in a complex hydraulic system and excessively large piston size. This solution, however, uses a wedge mechanism to convert the movement direction of the drive component 43 into the axial movement of the pressure rod 4, allowing the filling and pressurizing actions to be performed by different mechanisms. This not only simplifies the hydraulic cylinder structure but also achieves a force multiplication effect through mechanical wedge surface transmission, reducing the power requirement of the drive component 43. Furthermore, the rigid contact between the wedge and the wedge block 42 avoids the pressure leakage problem caused by seal wear in traditional hydraulic systems.

[0084] Through the above technical solution, this application achieves mechanical decoupling of the filling and pressurizing actions, allowing the pressurizing thrust to be precisely controlled through the wedge mechanism, effectively preventing secondary oxidation of the molten metal during the pressurization stage. The rigid contact characteristics of the wedge transmission structure reduce the response delay of the hydraulic system, ensuring the timeliness and stability of the pressurizing action. At the same time, the reset design of the compression spring 45 improves the reliability of the mechanism's action and reduces the equipment failure rate.

[0085] Furthermore, the pressurization step includes a formula for calculating the pressurization thrust, including...

[0086] ,

[0087] Where F represents the magnitude of the pressurized thrust. Indicates the thrust of the driving component. This indicates the friction angle between the wedge and the pressure seat contact surface. The friction angle between the first and second wedge surfaces. The wedge angle for applying pressure to the locking wedge.

[0088] The formula for calculating the pressurizing thrust refers to a mechanical relationship established based on the wedge transmission principle. It can be derived using trigonometric functions and the coefficient of friction to accurately calculate the actual thrust applied by the pressure rod 4. The thrust of the driving component 43 refers to the original driving force output by the hydraulic cylinder or servo motor, which can be monitored in real time using a pressure sensor and used as an input parameter for calculating the pressurizing thrust. The friction angle between the wedge and the pressure seat 44 contact surface refers to the angle parameter corresponding to the frictional resistance generated on the contact surface during transmission, which can be determined using material friction coefficient testing experiments. The friction angle between the first and second wedge surfaces refers to the frictional characteristic parameter between the contact surface of the pressurizing wedge 41 and the wedge block 42, which can be achieved using contact surface roughness control technology. The wedge angle of the locking pressurizing wedge 41 refers to the inclination angle of the working surface of the pressurizing wedge 41, which can be precisely machined using mechanical processing techniques and directly affects the transmission efficiency.

[0089] Specifically, during the pressurization process, the thrust output by the drive component 43 is converted into a force value through a wedge mechanism. By establishing a mechanical model that includes frictional losses, the input thrust of the drive component 43 is converted into the effective output force of the pressurizing rod 4. When performing the pressurization operation, the actual pressure value applied to the molten metal is accurately calculated by substituting the measured friction angle parameters and wedge angle parameters into the calculation formula. This calculation process can be corrected in real time by combining feedback data from the pressure sensor to ensure that the accuracy of the pressurized thrust application is controlled within the allowable error range.

[0090] In some specific embodiments, the thrust of the drive component 43 can be measured using a force sensor mounted on the piston rod of the hydraulic cylinder. The friction angle of the wedge contact surface can be obtained through material pairing experiments; for example, when using a friction pair of 45 steel and copper alloy, the friction angle is measured to be 5-8 degrees. The wedge angle parameter can be selected according to the equipment structural design requirements, for example, using a standard angle value of 15 degrees or 20 degrees. In practical applications, the angle parameter in the formula can be pre-stored in the control system, and used in conjunction with a displacement sensor to monitor the stroke position of the pressure rod 4 to achieve closed-loop control of the pressurizing thrust.

[0091] Compared to existing technologies, traditional pressurization processes lack precise mechanical calculation models, relying solely on empirical parameters to set pressurization pressure, which can easily lead to insufficient pressure or overload. This solution, by establishing a mechanical calculation formula that incorporates friction loss, accurately reflects the force transmission relationship under actual working conditions. Compared to empirical estimation methods, this calculation model can improve the accuracy of pressurization thrust control by an order of magnitude, while avoiding pressure fluctuations caused by errors in friction loss estimation. This precise control method allows for more scientific and reasonable parameter settings in the pressurization process, effectively solving the casting defects caused by inaccurate pressure control in traditional equipment.

[0092] Through the above technical solution, this application can accurately calculate the actual thrust value during the pressurization process, effectively eliminating the influence of friction loss in the transmission mechanism on the pressurization effect. This allows the molten metal to obtain stable and controllable pressurization pressure during the solidification stage, significantly improving the density and mechanical properties of the casting. Simultaneously, the application of the calculation formula simplifies the equipment debugging process; operators can directly set the drive parameters based on 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, providing a reliable guarantee for the mass production of high-quality extruded castings.

[0093] Furthermore, the formula for calculating the pressure in the injection chamber includes:

[0094] ,

[0095] Where p represents the pressure inside the injection chamber, and D represents the diameter of the pressure rod.

[0096] The pressure within the injection chamber refers to the force per unit area exerted by the hydraulic oil within the working chamber of the extrusion mechanism. This force can be monitored in real-time by the pressure sensor of the hydraulic system, and it directly affects the pressurization effect of the punch 2 on the molten metal. The magnitude of the pressurizing thrust refers to the axial force exerted by the pressure rod 4 on the hydraulic oil within the injection chamber, which can be calculated from the output torque of the servo motor. This parameter determines the final solidification pressure transmitted to the molten metal. The diameter of the pressure rod 4 refers to the cross-sectional dimension of the contact area between the pressure rod 4 and the rear cover 33 of the extrusion cylinder. A stepped shaft structure design can be adopted, and this dimensional parameter is positively correlated with the transmission efficiency of the pressurizing thrust.

[0097] Specifically, during 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 pressure rod 4 to the cross-sectional area of ​​the pressure rod 4. By establishing a mathematical relationship between pressure, pressurization thrust, and the diameter of the pressure rod 4, the solidification pressure of the molten metal after filling can be precisely controlled. For example, when the diameter of the pressure rod 4 is designed to be 80mm, under the condition that the pressurization thrust reaches 200kN, the pressure in the injection chamber can be accurately calculated to be 39.79MPa, thus providing a theoretical basis for the oil pressure control of the hydraulic system.

[0098] Compared to existing technologies, traditional equipment, lacking a pressure calculation formula, generally uses large-sized hydraulic cylinders to ensure pressure margin, resulting in bulky equipment and high energy consumption. This solution establishes a quantitative relationship between pressure and the parameters of the pressure rod 4, enabling the hydraulic system to match the optimal parameter combination according to actual working conditions. For example, under the same pressure thrust requirement, the volume of the hydraulic cylinder can be reduced by about 30% by adjusting the diameter of the pressure rod 4.

[0099] Through the above technical solution, this application effectively solves the structural complexity problem caused by the redundancy of the hydraulic system design in traditional extrusion casting equipment, and achieves precise matching between the size of the pressure rod 4 and the hydraulic thrust, which significantly reduces the equipment manufacturing cost and maintenance difficulty while ensuring the density of the casting.

[0100] Working principle:

[0101] The usage process of the extrusion casting apparatus involved in this application is as follows:

[0102] First, the feeding step is carried out. The extrusion rod 3 is in the lowest position, and the sealing plate 11 at the feed port 102 is opened. The molten metal rises from the holding furnace along the feeding channel 12 to the pressure chamber 1 under the action of air pressure. After reaching the set height in the pressure chamber 1 according to the set mass, the sealing plate 11 moves to close the feed port, and the molten metal in the channel flows back to the holding furnace.

[0103] Next, the filling operation is carried out. The hydraulic oil of the system enters the working chamber through the forward channel, pushing the extrusion rod 3 forward until the molten metal fills the mold cavity. The filling time is controlled by controlling the forward speed of the extrusion rod 3.

[0104] Next, the pressurization operation is performed. After filling is completed, the molten metal begins to solidify, and the piston rod speed rapidly decreases to zero. The molten metal completely fills the cavity. The solidified molten metal is compacted by applying pressure with a wedge, increasing the density of the die casting and obtaining a high-performance die casting. After the signal of increased forward resistance of the punch 2 is transmitted to the control system, the hydraulic valve is controlled to close the forward passage. At this time, the working chamber is a closed chamber. The wedge drive drives the pressure wedge 41 forward, which in turn causes the pressure rod 4 to squeeze the oil in the working chamber axially forward, increasing the oil pressure in the injection chamber and realizing the pressurization effect on the molten metal.

[0105] Then, the mold opening operation is performed, and the product is removed. After a certain cooling time, the moving mold 7 plate opens, and the pressure wedge 41 retracts to its original position under the action of the drive. The pressure rod 4 and the wedge block 42 move downward and close to the wedge surface of the wedge under the action of the compression spring 45. At the same time, the forward passage opens, and the system hydraulic oil enters the working chamber, causing the piston rod to move forward and carry the punch 2 out of the fixed mold 6 to discharge the excess material. The ejection device in the moving mold 7 ejects the casting from the mold, and the robot arm takes out the casting.

[0106] Finally, the system resets. The hydraulic oil in the system flows through the return channel to retract the extrusion rod 3 until it returns to its initial position, starting the next casting cycle.

[0107] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are within its protection scope. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within its protection scope.

Claims

1. A squeeze casting apparatus, characterized in that: include Pressure chamber (1), the pressure chamber (1) is fixedly connected to the fixed template (5), the pressure chamber (1) has a receiving cavity (101) for containing molten metal, the side of the pressure chamber (1) is provided with a feed port (102) and connected to a feeding channel (12), a sealing plate (11) is provided at the feed port (102), the sealing plate (11) is used to open or close the feed port (102); Punch (2), wherein the punch (2) and the pressure chamber (1) are in sliding fit; The extrusion mechanism includes an extrusion rod (3), and a punch (2) is fixedly connected to the end of the extrusion rod (3). The extrusion mechanism drives the extrusion rod (3) to move based on the hydraulic principle so that the punch (2) pushes the molten metal filling of the receiving cavity (101). The pressurizing mechanism drives the extrusion rod (3) to move to provide pressurizing thrust to the filled molten metal.

2. The extrusion casting apparatus according to claim 1, characterized in that: 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 in cooperation with the extrusion cylinder body (32), and the piston divides the working chamber. The front cover (31) of the extrusion cylinder is fixedly connected to the fixed template (5) for the injection chamber and the return chamber. A retraction channel (311) is formed on the front cover (31) of the extrusion cylinder, which is connected to the return chamber. A forward channel (331) is formed on the rear cover (33) of the extrusion cylinder, which is connected to the injection chamber. The retraction channel (311) and the forward channel (331) are supplied with hydraulic oil to drive the extrusion rod (3) to move axially.

3. The extrusion casting apparatus according to claim 2, characterized in that: A pressure hole is formed on the rear cover (33) of the extrusion cylinder. The pressure mechanism includes a pressure seat (44), a pressure rod (4), and a pressure drive assembly. The pressure seat (44) is fixedly connected to the rear cover (33) of the extrusion cylinder. The pressure rod (4) is slidably connected to the pressure seat (44). The pressure hole allows the pressure rod (4) to extend into it. When the pressure rod (4) moves toward the extrusion rod (3), the working chamber is sealed, and the pressure rod (4) squeezes the hydraulic oil in the injection chamber to push the extrusion rod (3) to pressurize the molten metal.

4. The extrusion casting apparatus according to claim 3, characterized in that: The pressurizing drive assembly includes a drive member, a pressurizing wedge (41), and a wedge block (42). The pressurizing wedge (41) is slidably connected to the pressurizing seat (44). A first wedge surface is formed on the pressurizing wedge (41). The wedge block (42) is fixedly connected to the pressurizing rod (4). A second wedge surface is formed on the wedge block (42). The first wedge surface and the second wedge surface are in sliding contact. The drive member is fixedly connected to the pressurizing seat (44). The drive member is used 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 extrusion casting apparatus according to claim 4, characterized in that: The pressurizing mechanism is provided with a compression spring (45), which provides an elastic force to 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. The extrusion casting apparatus according to claim 2, characterized in that: The formula for calculating the pressurized thrust includes ， Where F represents the magnitude of the pressurized thrust. Indicates the thrust of the driving component. This indicates the friction angle between the wedge and the pressure seat contact surface. The friction angle between the first and second wedge surfaces. The wedge angle is the angle of the pressure wedge.

7. The extrusion casting apparatus according to claim 6, characterized in that: The pressure calculation formula for the injection chamber includes: ， Where p represents the pressure inside the injection chamber, and D represents the diameter of the pressure rod.

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