Low pressure casting mold and process for high strength aluminum alloy support assembly

Abstract

The present application relates to the technical field of aluminum alloy low-pressure casting, in particular to a low-pressure casting mold and process for a high-strength aluminum alloy support assembly, a bottom mold assembly is provided with a C-shaped channel in the wall body and a lower positioning column is sleeved on the top surface, an upper mold assembly is provided with a C-shaped channel in the wall body and an upper positioning column is sleeved on the bottom surface, four side mold assemblies are respectively provided with vertical flow channels in the wall body and are respectively provided with positioning holes on the top and bottom surfaces; a side mold closing assembly is used to drive the side mold assemblies to move synchronously in the radial direction to complete lateral mold closing, and a mold pressing assembly is used to press and fix the top surface of the upper mold assembly after vertical mold closing. The C-shaped channel of the bottom mold assembly, the vertical flow channels of the side mold assemblies and the C-shaped channel of the upper mold assembly form a gradient cooling system, and the cooling liquid flows sequentially from bottom to top. The casting process includes mold closing, mold locking, inert gas filling and vacuumizing, gradient cooling starting, low-pressure filling, pressure increasing and holding, and mold opening and demolding. The mold closing locking force and cooling uniformity are improved to improve the casting quality.

Description

Technical Field

[0001] This invention relates to the field of low-pressure casting technology for aluminum alloys, specifically to a low-pressure casting mold and process for a high-strength aluminum alloy support component. Background Technology

[0002] With the increasing demand for lightweighting in new energy vehicles and the rising performance requirements for structural components in the aerospace field, the application of high-strength aluminum alloy (such as Al-Si-Cu-Mg and Al-Zn-Mg systems) support components (such as chassis swing arms, shock absorber towers, and fuselage frame connectors) is becoming increasingly widespread. These support components typically feature thin walls, complex internal cavities, and multi-ribbed structures, and have extremely high requirements for mechanical properties and density.

[0003] Traditional gravity casting processes suffer from defects such as unstable mold filling, cold shuts, shrinkage cavities, and porosity when forming complex thin-walled parts. Furthermore, the wide crystallization temperature range of aluminum alloys leads to poor feeding effects, resulting in low yields. Low-pressure casting is widely used due to its stable mold filling and ease of forming complex castings. However, in actual production, especially for manufacturing high-strength aluminum alloy support components, existing low-pressure casting technology still has the following drawbacks: (a) Insufficient clamping force in mold closing: Mold assembly generally includes upper mold, lower mold and side mold. In the pressure-increasing solidification stage of low-pressure casting, the cavity is subjected to high pressure. Traditional pneumatic or hydraulic mold closing mechanisms may produce a slight "mold bulging" phenomenon due to pressure fluctuations or insufficient rigidity during long-term pressure holding, resulting in flash on the parting surface. This not only affects dimensional accuracy, but more seriously, it will destroy the closed state of the cavity, leading to pressure leakage and failure to establish effective crystallization pressure, thereby weakening the feeding effect. (ii) Uneven temperature field distribution problem: Uneven cooling can easily cause local hot spots and residual stress in the product.

[0004] Therefore, there is an urgent need to develop a special mold and process that can ensure high rigidity of the mold and facilitate uniform cooling. Summary of the Invention

[0005] The purpose of this invention is to provide a low-pressure casting mold and process for a high-strength aluminum alloy support component, which solves the problems of uneven cooling and insufficient clamping force in existing low-pressure casting molds.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a low-pressure casting mold for a high-strength aluminum alloy support component, comprising a double-layer frame with two parallel upper and lower platforms on the top and a space for accommodating a heat-holding furnace at the bottom; a bottom mold assembly fixed to the lower platform with a liquid injection hole in the center of the mold cavity, and a C-shaped channel in the wall surrounding the mold cavity of the bottom mold assembly, with lower positioning posts fitted on the top surface of the bottom mold assembly near its four edges; four side mold assemblies with vertical flow channels on the outer side of their mold cavities and positioning holes on their top and bottom surfaces; an upper mold assembly located below the upper platform with a C-shaped channel in the wall surrounding the mold cavity, and upper positioning posts fitted on the bottom surface of the upper mold assembly near its four edges; and a side-closing mold assembly located outside the four side mold assemblies. The support member is used to drive the side mold assembly to move synchronously radially to complete the lateral mold closing and make the positioning holes on the top and bottom surfaces directly align with the upper and lower positioning posts, respectively; the telescopic cylinder is vertically installed on the upper platform and is used to push and pull the upper mold assembly; the vertical guide rod is located around the side mold closing assembly and is fixed vertically to the double-layer platform; springs are respectively fitted at the bottom of the vertical guide rod; the pressure mold assembly is used to press and fix the top surface of the upper mold assembly after vertical mold closing; the outer edge of the upper mold assembly and the outer support member of the side mold assembly are slidably sleeved on the top and middle of the vertical guide rod, respectively; coolant flows sequentially from bottom to top in the C-shaped channel of the bottom mold assembly, the vertical flow channel of the side mold assembly, and the C-shaped channel of the upper mold assembly.

[0007] Preferably, it further includes a disc-shaped cavity and a guide support. The disc-shaped cavity includes a cylinder, an annular plate fixed to the bottom of the inner cavity of the cylinder, multiple ear plates fixed to the outer peripheral wall of the cylinder, and a side cavity connected to one side of the cylinder. The ear plates are provided with guide holes for sliding engagement with the vertical guide rod. The guide support includes a cover plate whose outer edge is sewn to the outer edge of the top of the cylinder, a side plate fixed to one side of the cover plate and whose outer edge is sewn to the outer edge of the top of the side cavity, a square cylinder whose bottom end is fixedly sleeved on the cover plate, and multiple sliding sleeves fitted around the side walls of the square cylinder. The side mold assembly includes an inner ring. The system includes a slewing bearing fixed to the top surface of the circular plate, four pins with their bottom ends sleeved on the top surface of the outer ring of the slewing bearing, an arc-shaped beam with its outer end rotatably sleeved on the top of the pins and its inner end rotatably connected to the outer wall of the side mold assembly, and a power component that drives the outer ring of the slewing bearing to rotate. The outer wall of the side mold assembly is fixed with a side guide rod that is slidably sleeved and matched with the sliding sleeve. A driving component is installed on the top surface of the side circular plate. A gear is fixedly mounted on the power output shaft of the driving component extending into the side circular cavity. The slewing bearing is an external gear type slewing bearing, and its outer ring teeth mesh with the gear.

[0008] Preferably, a cooling water cavity is provided on the lower side of the annular plate. The cooling water cavity includes an annular support plate whose outer edge is fixed to the bottom surface of the annular plate, a bottom annular cavity fixed to the inner edge of the bottom surface of the annular support plate, and an upper annular cavity fixed to the inner edge of the top surface of the annular support plate. The inner peripheral wall of the bottom annular cavity is provided with water outlets that are respectively connected to the bottom ends of the vertical flow channels in the four side mold assemblies through telescopic pipes. The inner peripheral wall of the upper annular cavity is provided with water return ports that are respectively connected to the top ends of the vertical flow channels in the four side mold assemblies through telescopic pipes. The bottom surface of the bottom annular cavity is fitted with a water inlet connector whose bottom end is connected to the output end of the C-shaped channel in the bottom mold assembly through a telescopic pipe. The top surface of the upper annular cavity is fitted with a water outlet connector whose top end is connected to the C-shaped channel in the upper mold assembly through a telescopic pipe.

[0009] Preferably, the side mold assembly includes a side module and a side plate with a mold cavity in the middle of the inner side wall. The positioning holes are respectively located on both sides of the middle of the top and bottom surfaces of the side module. A square groove is provided on the inner side of the outer edge of the outer side wall of the side module. A sink groove is provided in the center of the inner end face of the square groove. A return water groove and a water inlet groove are respectively provided in the horizontal direction at the top and bottom ends of the inner end face of the sink groove. A plurality of vertically extending strip-shaped flow channels are uniformly provided on the inner end face of the sink groove between the return water groove and the water inlet groove. The side plate is fixedly nested in the square groove. A square platform that is matched with the sink groove is integrally formed on the inner side wall of the side plate. A water inlet short pipe II and a water outlet short pipe II are respectively sleeved on the side plate at the middle positions of the water inlet groove and the return water groove. An ear seat that is rotatably connected to the inner end of the arc beam is fixed in the middle of the outer side wall of the side plate. The side guide rod is vertically fixed to the outer side wall of the side plate.

[0010] Preferably, the bottom mold assembly includes a bottom module with a mold cavity in the middle of the top surface and the outer edge fixed to the lower platform, and a sealing plate. The bottom ends of the lower positioning posts are respectively sleeved on the outer edges of the top surface of the bottom module. A rectangular groove is provided on the inner side of the outer edge of one side wall of the bottom module. A water return cavity and a water inlet cavity are respectively provided on the front and rear sides of the middle of the inner end face of the rectangular groove. The bottom module has two U-shaped channels with two ports respectively connected to the water return cavity and the water inlet cavity in the other three sides of the wall. The sealing plate is fitted with a water outlet short pipe and a water inlet short pipe respectively at the positions corresponding to the water return cavity and the water inlet cavity.

[0011] Preferably, the upper mold assembly includes an upper module with a mold cavity in the middle of the bottom surface and a sealing plate II. The top of the upper module is provided with multiple radial strips. The outer ends of the radial strips are provided with guide holes I that are slidably fitted with the vertical guide rod. The inner side of the outer edge of one side wall of the upper module is provided with a rectangular groove II. The front and rear sides of the middle of the inner end face of the rectangular groove II are respectively provided with a water inlet cavity II and a water return cavity II. The walls of the other three sides of the upper module are provided with two U-shaped channels II with two ports respectively connected to the water return cavity II and the water inlet cavity II. The sealing plate II is fitted with a water outlet short pipe III and a water inlet short pipe III at the positions corresponding to the positions of the water return cavity II and the water inlet cavity II, respectively. The upper positioning posts are respectively fitted at the four edges of the bottom surface of the upper module. The top surface of the upper module is fitted with an exhaust valve at the position corresponding to the mold cavity.

[0012] Preferably, the top surface of the upper module cavity is provided with a sleeve hole, and the exhaust valve includes a miniature electric cylinder, a sleeve with its top fixed to the bottom surface of the piston cylinder of the miniature electric cylinder and its bottom fixedly fitted into the sleeve hole, a push rod disposed in the inner cavity of the sleeve and its top fixedly connected to the bottom end of the piston rod of the miniature electric cylinder, a plug fixed to the bottom end of the push rod and slidably fitted with the bottom end of the sleeve hole, an exhaust nozzle fixedly connected to the side wall of the top end of the sleeve, and a fixing plate fixedly fitted to the sleeve near the top end and fixedly connected to the top surface of the upper module.

[0013] Preferably, the double-layer platform includes a platform, legs fixedly supported at the four corners of the bottom surface of the platform, vertical beams with their bottom ends fixed to both sides of the top surface of the platform, and a circular plate parallel to the platform and whose bottom surface is fixedly connected to the top of the vertical beams. The platform has a through hole in the middle that matches the lifting pipe. The bottom end of the telescopic cylinder piston is fixed to the top surface of the circular plate, and the circular plate has a through hole in the middle that matches the sliding sleeve of the telescopic cylinder piston rod.

[0014] Preferably, the molding assembly includes a second slewing bearing whose outer ring is fixed to the outer edge of the bottom surface of the circular plate, a plurality of inverted L-shaped plate frames whose top ends are fixed to the bottom surface of the inner rotating ring of the second slewing bearing, and a slot fixed to the side wall of the inverted L-shaped plate frame and engaging with the vertical guide rod. The top surface of the circular plate is provided with a top drive assembly. The second slewing bearing is an internal gear type slewing bearing. The top drive assembly includes a second drive component fixed to one side of the top surface of the circular plate and whose power output shaft passes through the circular plate, and a second gear fixedly fitted to the bottom end of the power output shaft of the second drive component and meshing with the inner ring teeth of the second slewing bearing.

[0015] A casting process for a low-pressure casting mold of a high-strength aluminum alloy support component includes the following steps: S1. The four side mold components are moved radially in sync by the side mold assembly to complete the side mold closing; S2. The upper mold assembly is pressed downward by the telescopic cylinder, so that the lower positioning post and the upper positioning post are respectively inserted into the positioning hole to complete the vertical mold closing, and the mold pressing assembly is used for vertical clamping. S3. After the mold is closed, inert gas is sequentially injected into the mold cavity through the injection hole and the venting valve, and then a vacuum is drawn. S4. Gradient cooling is initiated through the C-shaped channels of the bottom mold assembly, the vertical flow channels of the side mold assembly, and the C-shaped channels of the upper mold assembly. S5. Preheat the aluminum alloy liquid to 700~750℃, and after refining, pour it into the heat preservation furnace. S6. Use inert gas as the medium and perform low-pressure filling at a pressure of 0.02~0.03 MPa for a filling time of 10~20 s; S7. Increase the pressure to 0.08~0.10 MPa and hold for 25~35 seconds; S8. After the pressure holding period ends and the casting cools for 30-40 seconds, the mold is opened and the casting is demolded.

[0016] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention relates to a low-pressure casting mold and process for a high-strength aluminum alloy support component. The side mold assembly drives four side mold assemblies to move radially synchronously to complete the side mold closing, which solves the problems of asynchronous movement and mold jamming that are easy to occur in the traditional hydraulic cylinder direct push method. The side mold closing accuracy is high and the side flash is reduced.

[0017] 2. The low-pressure casting mold and process for a high-strength aluminum alloy support component involved in this invention ensures the stability of the upper mold component and the side mold component support during movement by setting up vertical guide rods, springs and pressure mold components, and provides reliable lateral and vertical locking forces after mold closing, ensuring the sealing of the mold under high pressure filling.

[0018] 3. The low-pressure casting mold and process for a high-strength aluminum alloy support component involved in this invention achieves sequential flow of coolant from bottom to top by setting independent cooling channels and cooling water chambers for the bottom mold component, side mold component, and upper mold component, thus forming a gradient cooling system. This system can control the sequential cooling of the casting from bottom to top, effectively eliminating shrinkage porosity and shrinkage defects.

[0019] 4. The low-pressure casting mold and process for a high-strength aluminum alloy support component involved in this invention can assist in vacuuming and inert gas replacement before filling by actively controlled exhaust valve, which can avoid oxidation. After filling, timely sealing helps to reduce porosity in the casting and improve the density of the structure. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the entire invention; Figure 2 This is a three-dimensional structural diagram of the double-layer platform of the present invention; Figure 3 This is an exploded structural diagram of the bottom mold assembly of the present invention; Figure 4 This is a three-dimensional structural diagram of the base module of the present invention; Figure 5 This is an exploded structural diagram of the side mold assembly of the present invention; Figure 6 This is a three-dimensional structural diagram of the side module of the present invention; Figure 7 This is a three-dimensional structural diagram of the side plate of the present invention; Figure 8 This is an exploded structural diagram of the upper mold component of the present invention; Figure 9 This is a three-dimensional structural diagram of the module of the present invention; Figure 10 This is a three-dimensional structural schematic diagram of the exhaust valve component of the present invention; Figure 11 This is a three-dimensional structural diagram of the disc-shaped cavity of the present invention; Figure 12 This is a three-dimensional structural diagram of the guide support component of the present invention; Figure 13 This is an exploded structural diagram of the side-clamping mold assembly of the present invention; Figure 14 This is a three-dimensional structural schematic diagram of the molding assembly of the present invention; Figure 15 This is a three-dimensional structural schematic diagram of the top drive assembly of the present invention; Figure 16 This is a three-dimensional structural diagram of the cooling water cavity of the present invention.

[0021] In the diagram: 1-Double-layer frame; 1.1-Platform; 1.2-Support leg; 1.3-Vertical beam; 1.4-Circular plate; 2-Bottom mold assembly; 2.1-Bottom module; 2.1.1-Injection hole; 2.1.2-Rectangular groove one; 2.1.3-U-shaped channel one; 2.1.4-Water inlet chamber one; 2.1.5-Water return chamber one; 2.1.6-Lower positioning post; 2.2-Sealing plate one; 2.3-Water inlet short pipe one; 2.4-Water outlet short pipe one; 3-Side mold assembly; 3.1-Side module; 3.1.1-Square groove; 3.1.2-Settling tank; 3.1.3-Inlet water tank; 3.1.4-Return water tank; 3.1.5-Strip flow channel; 3.1.6-Positioning hole; 3.2-Side plate; 3.2.1-Square plate; 3.2.2-Square platform; 3.2.3-Second short inlet pipe; 3.2.4-Second short outlet pipe; 3.2.5-Ear seat; 3.2.6-Side guide rod; 4-Upper mold assembly; 4.1-Upper module; 4.1.1-Radial strip; 4.1.2-Guide hole one; 4.1.3-Rectangular groove two; 4.1.4-U-shaped channel two; 4.1.5-Water inlet cavity two; 4.1.6-Water return cavity two; 4.1.7-Upper positioning post; 4.1.8-Sleeve hole; 4.2-Sealing plate two; 4.3-Water inlet short pipe three; 4.4-Water outlet short pipe three; 4.5-Exhaust valve; 4.5.1-Miniature electric cylinder; 4.5.2-Sleeve; 4.5.3-Push rod; 4.5.4-Plug; 4.5.5-Exhaust nozzle; 4.5.6-Fixing plate; 5-Disc-shaped cavity; 5.1-Cylinder; 5.2-Annular plate; 5.3-Ear plate; 5.4-Guide hole two; 5.5-Side circular cavity; 6-Guide support component; 6.1-Cover plate; 6.2-Side circular plate; 6.3-Square cylinder; 6.4-Sliding sleeve; 7-Telescopic cylinder; 8-Vertical guide rod; 9-Spring; 10-Side mold assembly; 10.1-Slewing bearing 1; 10.2-Arc beam; 10.3-Pin; 10.4-Drive component 1; 10.5-Gear 1; 11-Pressure molding assembly; 11.1-Slewing bearing II; 11.2-Inverted L-shaped plate frame; 11.3-Card slot; 12-Top drive assembly; 12.1-Drive component two; 12.2-Gear two; 13-Cooling water chamber; 13.1-Annular support plate; 13.2-Bottom annular cavity; 13.3-Inlet connector; 13.4-Outlet; 13.5-Upper annular cavity; 13.6-Return port; 13.7-Outlet connector. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1, please refer to Figure 1-16This invention provides a technical solution: a low-pressure casting mold for a high-strength aluminum alloy support component. The double-layer frame 1 includes a platform 1.1, legs 1.2 fixedly supported at the four corners of the bottom surface of the platform 1.1, vertical beams 1.3 with their bottom ends fixed to both sides of the top surface of the platform 1.1, and a circular plate 1.4 parallel to the platform 1.1 and fixedly connected to the top of the vertical beams 1.3 at its bottom. The platform 1.1 has a through hole in its center that matches a riser pipe. The piston cylinder of the telescopic cylinder 7 has its bottom end fixed to the top surface of the circular plate 1.4, and the circular plate 1.4 has a through hole in its center that matches a slidingly fitted piston rod of the telescopic cylinder 7. In other words, the double-layer frame 1 has two parallel platform surfaces at the top and a space at the bottom for accommodating a heat-preserving furnace.

[0024] The bottom mold assembly 2 includes a bottom module 2.1 with a mold cavity in the middle of the top surface and the outer edge fixed to the middle of the top surface of the platform 1.1 by bolts, etc., and a sealing plate 2.2. The bottom ends of the lower positioning posts 2.1.6 are respectively sleeved on the outer edges of the top surface of the bottom module 2.1. A rectangular groove 2.1.2 is provided on the inner side of the outer edge of one side wall of the bottom module 2.1. The front and rear sides of the middle of the inner end face of the rectangular groove 2.1.2 are respectively provided with a water return cavity 2.1.5 and a water inlet cavity 2.1.4. The other three sides of the bottom module 2.1 have two U-shaped channels 2.1.3 with two ports connected to the water return cavity 2.1.5 and the water inlet cavity 2.1.4 respectively. That is, the U-shaped channel 2.1.3, the water return cavity 2.1.5 and the water inlet cavity 2.1.4 form a C-shaped channel structure. The sealing plate 2.2 is fitted with a water outlet short pipe 2.4 and a water inlet short pipe 2.3 at the positions corresponding to the return water chamber 2.1.5 and the inlet water chamber 2.1.4, respectively. The sealing plate 2.2 is fixedly connected to the outer edge of the rectangular groove 2.1.2 by bolts and is equipped with a sealing gasket. The bottom mold assembly 2 has a liquid injection hole 2.1.1 in the middle of the mold cavity. The liquid riser pipe at the top of the heat preservation furnace passes through the perforation in the middle of the platform 1.1 and is fitted with the liquid injection hole 2.1.1. The water inlet short pipe 2.3 is connected to the output end of the coolant pumping equipment through a pipe. The coolant enters the inlet water chamber 2.1.4 through the water inlet short pipe 2.3, and then enters the U-shaped channel 2.1.3. The coolant enters the return water chamber 2.1.5 from the other end of the U-shaped channel 2.1.3, and finally flows out from the water outlet short pipe 2.4. The C-shaped channel structure surrounds the mold cavity to provide uniform and sufficient cooling to the bottom mold cavity.

[0025] The four side mold components 3 each include a side module 3.1 with a mold cavity in the middle of its inner sidewall and a side plate 3.2. Positioning holes 3.1.6 are respectively provided on both sides of the middle of the top and bottom surfaces of the side module 3.1. A square groove 3.1.1 is provided on the inner side of the outer edge of the outer side wall of the side module 3.1. A recessed groove 3.1.2 is provided in the center of the inner end face of the square groove 3.1.1. A return water groove 3.1.4 and a water inlet groove 3.1.3 are respectively provided horizontally at the top and bottom ends of the inner end face of the recessed groove 3.1.2. The inner end face of the recessed groove 3.1.2 is located between the return water groove 3.1.4 and the water inlet groove 3.1.3. The unit has several vertically extending strip-shaped flow channels 3.1.5 evenly spaced. Side plates 3.2 are fixedly nested within square grooves 3.1.1. The inner wall of side plate 3.2 is integrally formed with square platforms 3.2.2 that snap into and match the settling tank 3.1.2. Inlet short pipes 3.2.3 and outlet short pipes 3.2.4 are respectively fitted onto the middle of the inlet groove 3.1.3 and return groove 3.1.4 of side plate 3.2. An ear seat 3.2.5 is fixed to the middle of the outer wall of side plate 3.2. A side guide rod 3.2.6 is vertically fixed to the outer wall of side plate 3.2. The outer edge of side plate 3.2 is bolted and fixedly connected to the outer edge of square groove 3.1.1, and a sealing gasket is installed. Both side walls of side module 3.1 have a 45° bevel. The coolant enters the inlet tank 3.1.3 through the inlet short pipe 2 3.2.3, then flows upward into the return tank 3.1.4 through the strip flow channel 3.1.5, and finally flows out through the outlet short pipe 2 3.2.4.

[0026] The upper mold assembly 4 includes an upper module 4.1 with a mold cavity in the center of its bottom surface and a sealing plate 4.2. The top of the upper module 4.1 has multiple radial strips 4.1.1, and the outer ends of the radial strips 4.1.1 have guide holes 4.1.2. The inner side of the outer edge of one side wall of the upper module 4.1 has a rectangular groove 4.1.3. The sealing plate 4.2 and the outer edge of the rectangular groove 4.1.3 are fixedly connected by bolts and fitted with a sealing gasket. The top center of the upper module 4.1 is fixedly connected to the bottom end of the piston rod of the telescopic cylinder 7. The inner end face of the rectangular groove 4.1.3 has an inlet chamber 4.1.5 and a return chamber 4.1.6 on the front and rear sides respectively. The upper module 4.1 has two U-shaped channels 4.1.4 on the other three sides of the wall, which are connected to the return chamber 4.1.6 and the inlet chamber 4.1.5 respectively. The U-shaped channel 4.1.4, the return chamber 4.1.6 and the inlet chamber 4.1.5 form a C-shaped channel structure. The sealing plate 4.2, corresponding to the positions of the return water chamber 4.1.6 and the inlet water chamber 4.1.5, is fitted with a short outlet pipe 4.4 and a short inlet pipe 4.3, respectively. That is, the coolant enters the inlet water chamber 4.1.5 through the short inlet pipe 4.3, then enters the U-shaped channel 4.1.4. The coolant then enters the return water chamber 4.1.6 from the other end of the U-shaped channel 4.1.4, and finally flows out through the short outlet pipe 4.4. The C-shaped channel structure surrounds the mold cavity to provide uniform and sufficient cooling to the upper mold cavity. Upper positioning pins 4.1.7 are fitted around the bottom edges of the upper module 4.1. An exhaust valve 4.5 is fitted on the top surface of the upper module 4.1, corresponding to the position of the mold cavity. The upper module 4.1 has a sleeve hole 4.1.8 on the top surface of the mold cavity. The exhaust valve component 4.5 includes a miniature electric cylinder 4.5.1, a sleeve 4.5.2 with its top fixed to the bottom surface of the piston cylinder of the miniature electric cylinder 4.5.1 and its bottom fixedly fitted into the sleeve hole 4.1.8, a push rod 4.5.3 located in the inner cavity of the sleeve 4.5.2 and its top fixedly connected to the bottom end of the piston rod of the miniature electric cylinder 4.5.1, a plug 4.5.4 fixed to the bottom end of the push rod 4.5.3 and slidably fitted with the bottom end of the sleeve hole 4.1.8, an exhaust nozzle 4.5.5 fixedly connected to the top side wall of the sleeve 4.5.2, and a fixing plate 4.5.6 fixedly fitted into the sleeve 4.5.2 near the top end and fixedly connected to the top surface of the upper module 4.1. When the mold cavity is evacuated and vented, the micro electric cylinder 4.5.1 pushes the push rod 4.5.3 downward, causing the plug 4.5.4 to extend downward into the sleeve hole 4.1.8, so as to ensure that the inner cavity of the sleeve 4.5.2 is connected to the mold cavity; when the micro electric cylinder 4.5.1 pulls the push rod 4.5.3 upward, the plug 4.5.4 will be inserted into the bottom of the sleeve hole 4.1.8, at which time the bottom surface of the plug 4.5.4 is flush with the top surface of the mold cavity.

[0027] The disc-shaped cavity 5 includes a cylinder 5.1, an annular plate 5.2 fixed to the bottom of the inner cavity of the cylinder 5.1, multiple ear plates 5.3 fixed to the outer peripheral wall of the cylinder 5.1, and a side cavity 5.5 connected to one side of the cylinder 5.1. The ear plate 5.3 is provided with a guide hole 5.4.

[0028] The guide support 6 includes a cover plate 6.1 whose outer edge is sewn to the outer edge of the top of the cylinder 5.1, a side circular plate 6.2 fixed to one side of the cover plate 6.1 and whose outer edge is sewn to the outer edge of the top of the side circular cavity 5.5, a square cylinder 6.3 whose bottom end is fixedly sleeved on the cover plate 6.1, and multiple sliding sleeves 6.4 sleeved on the four sides of the square cylinder 6.3. The side guide rods 3.2.6 are respectively slidably sleeved in the sliding sleeves 6.4.

[0029] The side mold assembly 10 includes a slewing bearing 10.1 with its inner ring fixed to the top surface of the annular plate 5.2, four pins 10.3 with their bottom ends sleeved on the top surface of the outer ring of the slewing bearing 10.1, an arc-shaped beam 10.2 with its outer end rotatably sleeved on the top of the pins 10.3 and its inner end rotatably connected to the outer wall lug 3.2.5 of the side mold assembly 3, and a power component for driving the slewing bearing 10.1 to rotate the outer ring. A drive component 10.4 is mounted on the top surface of the side circular plate 6.2. The drive component 10.4 extends into the side circular cavity 5.5 and has a gear 10.5 fixedly mounted on its power output shaft. The slewing bearing 10.1 is an external gear type slewing bearing, and its outer ring teeth mesh with the gear 10.5. That is, the driving component 10.4 drives the outer ring of the slewing bearing 10.1 to rotate via the gear 10.5. The slewing bearing 10.1 pushes the corresponding side mold assembly 3 to move radially along the side via the arc beam 10.2. The four side mold assemblies 3 move radially synchronously to complete the lateral mold closing process. After the lateral mold closing process is completed, the positioning holes 3.1.6 on the top and bottom surfaces of the side module 3.1 are respectively aligned with the upper positioning post 4.1.7 and the lower positioning post 2.1.6.

[0030] The vertical guide rod 8 is located around the side mold assembly 10 and its top and bottom ends are fixedly connected to the circular plate 1.4 and the platform plate 1.1, respectively. Springs 9 are respectively fitted onto the bottom of the vertical guide rod 8. Guide hole 1 4.1.2 is slidably fitted onto the top of the vertical guide rod 8, and guide hole 2 5.4 is slidably fitted onto the bottom of the vertical guide rod 8, with the bottom surface of the ear plate 5.3 supported on the top of the spring 9.

[0031] The cooling water cavity 13 includes an annular support plate 13.1 whose outer edge is fixed to the bottom surface of the annular plate 5.2, a bottom annular cavity 13.2 fixed to the inner edge of the bottom surface of the annular support plate 13.1, and an upper annular cavity 13.5 fixed to the inner edge of the top surface of the annular support plate 13.1. The inner peripheral wall of the bottom annular cavity 13.2 is provided with four water outlets 13.4, and the inner peripheral wall of the upper annular cavity 13.5 is provided with four water return ports 13.6. The bottom surface of the bottom annular cavity 13.2 is fitted with a water inlet connector 13.3, and the top surface of the upper annular cavity 13.5 is fitted with a water outlet connector 13.7. The inlet connector 13.3 is connected at its bottom end to the outlet short pipe 2.4 via a telescopic pipe, and the outlet connector 13.7 is connected at its top end to the inlet short pipe 4.3 via a telescopic pipe. The four outlets 13.4 are connected to the corresponding inlet short pipes 3.2.3 via telescopic pipes, and the four return ports 13.6 are connected to the corresponding outlet short pipes 3.2.4 via telescopic pipes. Coolant flowing from the bottom mold assembly 2 enters the bottom ring cavity 13.2 through the inlet connector 13.3, and then flows into the inlet short pipe 3.2.3 via the outlets 13.4. Coolant in the side module 3.1 flows into the upper ring cavity 13.5 via the outlet short pipe 3.2.4 and the return port 13.6, and then flows into the inlet short pipe 4.3 via the outlet connector 13.7. This constitutes a gradient cooling system, facilitating the control of sequential cooling of the casting from bottom to top and effectively eliminating shrinkage porosity and shrinkage defects.

[0032] The molding assembly 11 includes a slewing bearing 11.1 with its outer ring fixed to the outer edge of the bottom surface of the circular plate 1.4, multiple inverted L-shaped plate frames 11.2 with their top ends fixed to the bottom surface of the inner ring of the slewing bearing 11.1, and a slot 11.3 fixed to the side wall of the inverted L-shaped plate frame 11.2 and engaging with the vertical guide rod 8. The top surface of the circular plate 1.4 is provided with a top drive assembly 12. The slewing bearing 11.1 is an internal gear slewing bearing. The top drive assembly 12 includes a drive component 12.1 fixed to one side of the top surface of the circular plate 1.4 with its power output shaft passing through the circular plate 1.4, and a gear 12.2 fixedly fitted to the bottom end of the power output shaft of the drive component 12.1 and meshing with the inner ring teeth of the slewing bearing 11.1. That is, when the telescopic cylinder 7 presses down on the upper mold assembly 4, the upper mold assembly 4 first completes the mold closing with the side mold assembly 3, which has already completed the side mold closing, and then compresses the spring 9 downward to continue the mold closing between the bottom mold assembly 2 and the side mold assembly 3. After the mold is closed, the upper positioning pin 4.1.7 and the lower positioning pin 2.1.6 are respectively inserted into the corresponding positioning holes 3.1.6, thereby forming a lateral mold-locking effect on the side mold assembly 3. Subsequently, the driving component 12.1 drives the inner ring of the slewing bearing 11.1 to rotate through the gear 12.2, so that the inverted L plate frame 11.2 drives the slot 11.3 to be locked on the vertical guide rod 8, and the bottom surface of the slot 11.3 is pressed against the top surface of the upper module 4.1 to form a vertical mold-locking effect on the mold assembly after mold closing, which significantly improves the mold closing locking force.

[0033] Example 2, please refer to Figure 1-16This invention provides a technical solution: a casting process for a low-pressure casting mold of a high-strength aluminum alloy support component, comprising the following steps: S1. The four side mold components 3 are moved radially in sync by the side mold assembly 10 to complete the side mold closing; S2. The telescopic cylinder 7 pushes the upper mold assembly 4 downward, so that the lower positioning pin 2.1.6 and the upper positioning pin 4.1.7 are respectively inserted into the positioning hole 3.1.6 to complete the vertical mold closing, and the mold pressing assembly 11 is used for vertical clamping. S3. After mold closing, inert gas is sequentially injected into the mold cavity through the injection hole 2.1.1 and the venting valve 4.5, and then a vacuum is drawn. Among them, the inert gas used is argon, etc.; S4. Gradient cooling is initiated through the C-shaped channels of the bottom mold assembly 2, the vertical flow channels of the side mold assembly 3, and the C-shaped channels of the upper mold assembly 4. S5. Preheat the A356 aluminum alloy liquid to 720℃ and refine it for 10 minutes to refine the grains and remove gas, then pour it into the holding furnace. S6. Use inert gas as the medium and perform low-pressure filling at a pressure of 0.02~0.03 MPa for a filling time of 10~20 s; S7. Increase the pressure to 0.08~0.10 MPa and hold it for 25~35 s. During this period, the gradient cooling system continues to work, forcing the casting to solidify in the order from bottom to top and from side wall to center, ensuring that the hot spots are fully fed back. S8. After the pressure holding period ends and the casting cools for 30-40 seconds, the mold is opened and the casting is demolded.

[0034] That is, after the pressure holding is completed, the pressure inside the furnace is released. When the mold temperature sensor shows that the casting has cooled to below 150°C, the locking of the mold assembly 11 is released in sequence, and the vertical mold opening is completed by the contraction of the telescopic cylinder 7. Then, the side mold opening is completed by the side mold assembly 10, thus completing the demolding process.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-pressure casting mold for a high-strength aluminum alloy support component, characterized in that, include: Double-layer frame (1), with two parallel upper and lower table surfaces on the top and a space for accommodating the heat preservation furnace at the bottom; Bottom mold assembly (2) is fixed to the lower platform and has a liquid injection hole in the middle of the mold cavity. 2.1.1), the bottom mold assembly (2) is provided with a C-shaped channel in the wall outside the mold cavity, and the bottom mold assembly (2) is fitted with a lower positioning post (2.1.6) on the top surface near the four edges. Side mold assembly (3), the four side mold assemblies (3) are respectively provided with vertical flow channels on the outside of the mold cavity and positioning holes (3.1.6) on the top and bottom surfaces respectively. The upper mold assembly (4) is located below the upper platform and has C-shaped channels in the wall of the outer periphery of the mold cavity. The upper mold assembly (4) has upper positioning posts (4.1.7) fitted on the bottom surface near the four edges. A side mold assembly (10) is provided in the outer support of the four side mold assemblies (3) for driving the side mold assemblies (3) to move radially synchronously to complete the lateral mold closing and make the positioning holes (3.1.6) on the top and bottom surfaces respectively face the upper positioning post (4.1.7) and the lower positioning post (2.1.6). Telescopic cylinder (7) is vertically installed on the upper platform and is used to push and pull the upper mold assembly (4). Vertical guide rods (8) are provided on the periphery of the side mold assembly (10) and are respectively fixed vertically to the double-layer frame (1). Springs (9) are respectively fitted onto the bottom of the vertical guide rod (8); The molding assembly (11) is used to press and fix the top surface of the upper mold assembly (4) after vertical mold closing; The outer edge of the upper mold assembly (4) and the outer support of the side mold assembly (3) are respectively slidably sleeved on the top and middle of the vertical guide rod (8); Coolant flows sequentially from bottom to top in the C-shaped channel of the bottom mold assembly (2), the vertical flow channel of the side mold assembly (3), and the C-shaped channel of the upper mold assembly (4).

2. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 1, characterized in that: It also includes a disc-shaped cavity (5) and a guide support (6). The disc-shaped cavity (5) includes a cylinder (5.1), an annular plate (5.2) fixed to the bottom of the inner cavity of the cylinder (5.1), multiple ear plates (5.3) fixed to the outer peripheral wall of the cylinder (5.1), and a side cavity (5.5) connected to one side of the cylinder (5.1). The ear plate (5.3) is provided with a guide hole (5.4) that slides with the vertical guide rod (8). The guide support (6) includes a cover plate (6.1) whose outer edge is sewn to the outer edge of the top end of the cylinder (5.1), a side circular plate (6.2) fixed to one side of the cover plate (6.1) and whose outer edge is sewn to the outer edge of the top end of the side circular cavity (5.5), a square cylinder (6.3) whose bottom end is fixedly sleeved on the cover plate (6.1), and a plurality of sliding sleeves (6.4) fitted around the four sides of the square cylinder (6.3). The side mold assembly (10) includes The assembly includes a slewing bearing (10.1) with its inner ring fixed to the top surface of the circular plate (5.2), four pins (10.3) with their bottom ends sleeved on the top surface of the outer ring of the slewing bearing (10.1), an arc-shaped beam (10.2) with its outer end rotatably sleeved on the top of the pins (10.3) and its inner end rotatably connected to the outer wall of the side mold assembly (3), and a power component that drives the outer ring of the slewing bearing (10.1) to rotate. The outer side wall is fixed with a side guide rod (3.2.6) that is slidably fitted and matched with the sliding sleeve (6.4). The top surface of the side circular plate (6.2) is equipped with a drive component (10.4). The drive component (10.4) extends into the power output shaft in the side circular cavity (5.5) and is fixedly fitted with a gear (10.5). The slewing bearing (10.1) is an external tooth slewing bearing and its outer ring tooth meshes with the gear (10.5).

3. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 2, characterized in that: The lower side of the annular plate (5.2) is provided with a cooling water cavity (13). The cooling water cavity (13) includes an annular support plate (13.1) whose outer edge is fixed to the bottom surface of the annular plate (5.2), a bottom annular cavity (13.2) fixed to the inner edge of the bottom surface of the annular support plate (13.1), and an upper annular cavity (13.5) fixed to the inner edge of the top surface of the annular support plate (13.1). The inner peripheral wall of the bottom annular cavity (13.2) is provided with water outlets that are respectively connected to the bottom ends of the vertical flow channels in the four side mold assemblies (3) through telescopic pipes. The inner circumferential wall of the upper annular cavity (13.4) and the upper annular cavity (13.5) is provided with return water inlets (13.6) that are connected to the top of the vertical flow channels in the four side mold assemblies (3) through telescopic pipes. The bottom surface of the bottom annular cavity (13.2) is fitted with a water inlet connector (13.3) whose bottom end is connected to the output end of the C-shaped channel in the bottom mold assembly (2) through a telescopic pipe. The top surface of the upper annular cavity (13.5) is fitted with a water outlet connector (13.7) whose top end is connected to the C-shaped channel in the upper mold assembly (4) through a telescopic pipe.

4. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 2, characterized in that: The side mold assembly (3) includes a side module (3.1) with a mold cavity in the middle of its inner wall and a side plate (3.2). The positioning holes (3.1.6) are respectively provided on both sides of the middle of the top and bottom surfaces of the side module (3.1). The outer edge of the outer wall of the side module (3.1) is provided with a square groove. 3.1.1), the inner end face of the square groove (3.1.1) is provided with a recessed groove in the center ( ). 3.1.2), the inner end face of the settling tank (3.1.2) is provided with a return water tank (3.1.4) and an inlet water tank (3.1.3) in the horizontal direction at the top and bottom ends respectively, and the inner end face of the settling tank (3.1.2) is located at the return water tank (3.1.4). A plurality of vertically extending strip-shaped flow channels (3.1.5) are evenly provided between the water inlet (3.1.4) and the water inlet (3.1.3). The side plate (3.2) is fixedly nested in the square groove (3.1.1). The inner side wall of the side plate (3.2) is integrally formed with a square platform (3.2.2) that is matched with the settling trough (3.1.2). The side plate (3.2) is fitted with a second water inlet pipe (3.2.3) and a second water outlet pipe (3.2.4) respectively at the middle positions of the water inlet (3.1.3) and the return water trough (3.1.4). The middle of the outer side wall of the side plate (3.2) is fixed with an ear seat (3.2.5) that is rotatably connected to the inner end of the arc beam (10.2). The side guide rod (3.2.6) is vertically fixed to the outer side wall of the side plate (3.2).

5. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 1, characterized in that: The bottom mold assembly (2) includes a bottom module (2.1) with a mold cavity in the middle of the top surface and its outer edge fixed to the lower platform, and a sealing plate (2.2). The bottom ends of the lower positioning posts (2.1.6) are respectively sleeved on the outer edges of the top surface of the bottom module (2.1). A rectangular groove (2.1.2) is provided on the inner side of the outer edge of one side wall of the bottom module (2.1). A water return cavity (2.2) is provided on the front and rear sides of the middle of the inner end face of the rectangular groove (2.1.2). The bottom module (2.1) has two U-shaped channels (2.1.3) on the other three sides of the wall, which are respectively connected to the return water chamber (2.1.5) and the inlet water chamber (2.1.4). The sealing plate (2.2) is fitted with the outlet short pipe (2.4) and the inlet short pipe (2.3) at the positions corresponding to the return water chamber (2.1.5) and the inlet water chamber (2.1.4).

6. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 1, characterized in that: The upper mold assembly (4) includes an upper module (4.1) with a mold cavity in the middle of its bottom surface and a second sealing plate (4.2). The upper module (4.1) has multiple radial strips on its top. 4.1.1), the radial strips ( 4.1.1) The outer end is provided with a guide hole (4.1.2) that is slidably fitted with the vertical guide rod (8). The inner side of the outer edge of one side wall of the upper module (4.1) is provided with a rectangular groove (4.1.3). The front and rear sides of the middle of the inner end face of the rectangular groove (4.1.3) are respectively provided with a water inlet cavity (4.1.5) and a water return cavity (4.1.6). The walls of the other three sides of the upper module (4.1) are provided with two ports that are respectively connected to the water return cavity (4.1.6) and the water return cavity (4.1.6). The U-shaped channel 2 (4.1.4) of the water inlet cavity 2 (4.1.5), the sealing plate 2 (4.2) corresponding to the positions of the water return cavity 2 (4.1.6) and the water inlet cavity 2 (4.1.5) are respectively fitted with the water outlet short pipe 3 (4.4) and the water inlet short pipe 3 (4.3), the upper positioning post (4.1.7) is respectively fitted on the four edges of the bottom surface of the upper module (4.1), and the top surface of the upper module (4.1) corresponding to the position of the mold cavity is fitted with the exhaust valve (4.5).

7. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 6, characterized in that: The upper module (4.1) has a sleeve hole (4.1.8) on the top surface of the mold cavity. The exhaust valve (4.5) includes a miniature electric cylinder (4.5.1), a sleeve (4.5.2) with its top end fixed to the bottom surface of the piston cylinder of the miniature electric cylinder (4.5.1) and its bottom end fixedly fitted into the sleeve hole (4.1.8), a push rod (4.5.3) located in the inner cavity of the sleeve (4.5.2) and its top end fixedly connected to the bottom end of the piston rod of the miniature electric cylinder (4.5.1), a plug (4.5.4) fixed to the bottom end of the push rod (4.5.3) and slidably fitted with the bottom end of the sleeve hole (4.1.8), an exhaust nozzle (4.5.5) fixedly connected to the top side wall of the sleeve (4.5.2), and a fixing plate (4.5.6) fixedly fitted into the sleeve (4.5.2) near the top end and fixedly connected to the top surface of the upper module (4.1).

8. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 1, characterized in that: The double-layer platform (1) includes a platform (1.1), legs (1.2) fixedly supported at the four corners of the bottom surface of the platform (1.1), vertical beams (1.3) with their bottom ends fixed to both sides of the top surface of the platform (1.1), and a circular plate (1.4) parallel to the platform (1.1) and fixedly connected to the top of the vertical beams (1.3) at its bottom surface. The platform (1.1) has a through hole in the middle that matches the liquid lifting pipe. The piston cylinder of the telescopic cylinder (7) has its bottom end fixed to the top surface of the circular plate (1.4), and the circular plate (1.4) has a through hole in the middle that matches the piston rod of the telescopic cylinder (7).

9. The low-pressure casting mold for a high-strength aluminum alloy support assembly according to claim 8, characterized in that: The molding assembly (11) includes a second slewing bearing (11.1) whose outer ring is fixed to the outer edge of the bottom surface of the circular plate (1.4), a plurality of inverted L-shaped plate frames (11.2) whose top ends are fixed to the bottom surface of the inner ring of the second slewing bearing (11.1), and a slot (11.3) fixed to the side wall of the inverted L-shaped plate frame (11.2) and matched with the vertical guide rod (8). The top surface of the circular plate (1.4) is provided with a top drive assembly (12). The second slewing bearing (11.1) is an internal gear slewing bearing. The top drive assembly (12) includes a second drive component (12.1) fixed to one side of the top surface of the circular plate (1.4) and whose power output shaft passes through the circular plate (1.4), and a second gear (12.2) fixedly fitted to the bottom end of the power output shaft of the second drive component (12.1) and meshing with the inner ring teeth of the second slewing bearing (11.1).

10. A casting process using a low-pressure casting mold for a high-strength aluminum alloy support assembly as described in claim 6, characterized in that, Includes the following steps: S1. The four side mold assemblies (3) are moved radially in sync by the side mold assembly (10) to complete the side mold closing; S2. The upper mold assembly (4) is pressed downward by the telescopic cylinder (7) so that the lower positioning post (2.1.6) and the upper positioning post (4.1.7) are respectively inserted into the positioning hole (3.1.6) to complete the vertical mold closing, and the vertical clamping is performed by the pressure mold assembly (11). S3. After the mold is closed, inert gas is sequentially filled into the mold cavity through the injection hole (2.1.1) and the exhaust valve (4.5) and then evacuated. S4. Gradient cooling is initiated through the C-shaped channel of the bottom mold assembly (2), the vertical flow channel of the side mold assembly (3), and the C-shaped channel of the upper mold assembly (4). S5. Preheat the aluminum alloy liquid to 700~750℃, and after refining, pour it into the heat preservation furnace. S6. Use inert gas as the medium and perform low-pressure filling at a pressure of 0.02~0.03 MPa for a filling time of 10~20 s; S7. Increase the pressure to 0.08~0.10 MPa and hold for 25~35 seconds; S8. After the pressure holding period ends and the casting cools for 30-40 seconds, the mold is opened and the casting is demolded.

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