Die-casting vacuumizing structure

Abstract

The utility model discloses a die-casting vacuumizing structure, which belongs to the field of high-pressure casting and is characterized in that a valve body is provided with a through hole and a connecting hole communicated with the through hole, an exhaust pipe is mounted in the connecting hole, a groove is formed in the end face, far away from an oil cylinder, of the valve body, the through hole is formed in the groove, the valve body is further provided with a containing groove, the containing groove and the through hole are coaxially arranged, and the diameter of the containing groove is larger than that of the through hole. The rod body part of the valve rod is located in the through hole, the end cover is located at the top of the valve body, an air draft channel is formed among the side wall and the transition face of the end cover and the groove, the chamfer and the convex edge of the valve body, the oil cylinder drives the valve rod to move downwards in the axial direction relative to the valve body, the sectional area of the air draft channel is reduced, and when the side wall of the valve rod makes contact with the convex edge, the air draft channel is closed. At the moment, the oil cylinder does not completely return; the valve rod continues to move downwards until the end cover is completely located in the containing groove, at the moment, the oil cylinder completely retreats, effective sealing is carried out in advance in the oil cylinder retreating process, molten aluminum located on the upper portion of the end cover cannot enter the valve body, and the die-casting vacuumizing structure is prevented from being damaged.

Description

Technical Field

[0001] This utility model relates to the field of high-pressure casting, and in particular to a vacuum extraction structure for die casting. Background Technology

[0002] In recent years, the development of new energy vehicles has been rapid. New energy vehicles have put forward new requirements for structure, requiring lighter body, but also ensuring vehicle safety. As a result, a large number of automotive structural parts have adopted high-pressure casting of aluminum alloy.

[0003] In aluminum alloy high-pressure casting, the presence of a large amount of gas in the mold cavity leads to a high gas content in the product, directly affecting its performance. Furthermore, automotive structural parts require heat treatment to improve their mechanical properties; during heat treatment, gas is released, causing bubbling and affecting the product's appearance and performance. Therefore, it is necessary to minimize the gas content of the product. This has led to the development of advanced vacuum die casting technology, which removes gas from the mold cavity during the die casting process, eliminating or significantly reducing porosity and dissolved gases in the die casting, thereby improving the mechanical properties and surface quality of the die casting.

[0004] Currently, there are three main methods for vacuum casting: 1. hydraulic active valve, 2. mechanical valve, and 3. vacuum exhaust plate. For large or lightweight products requiring high vacuum levels, hydraulic active valves are primarily used. However, existing hydraulic active valves have either conical seals or a combination of straight and conical seals. Frequently, issues arise such as incomplete cylinder retraction or improper valve closing delay settings, leading to molten aluminum rushing into the vacuum valve and causing production failures. Utility Model Content

[0005] In order to overcome the shortcomings of the prior art, one of the objectives of this utility model is to provide a die-casting vacuum structure that can prevent molten aluminum from rushing into the vacuum valve due to the cylinder not retracting properly or the valve closing delay time being set improperly.

[0006] One of the objectives of this utility model is achieved through the following technical solution:

[0007] A die-casting vacuum structure includes a drive assembly, a valve stem, a vacuum valve, and a suction pipe. The drive assembly includes a hydraulic cylinder and an oil pipe communicating with the hydraulic cylinder. The valve stem is kinetically connected to the hydraulic cylinder. The vacuum valve includes a valve body with a through hole coaxially arranged with the valve stem and a connecting hole communicating with the through hole. The suction pipe is installed in the connecting hole. The end face of the valve body away from the hydraulic cylinder has a groove, and the through hole is disposed in the groove. The top of the through hole has a chamfered edge, and the chamfer and the through hole intersect to form a convex edge. The valve body also has a receiving groove, which is coaxially arranged with the through hole. The diameter of the receiving groove is larger than the diameter of the through hole. Along the axial direction, the receiving groove is located between the groove and the through hole. Between the connecting holes, the valve stem includes a rod body and an end cap located at the end of the rod body. The end cap includes a side wall and a transition surface. The transition surface extends from the bottom of the side wall to the end of the valve stem. The rod body portion is located in the through hole, and the end cap is located at the top of the valve body. The side wall and transition surface of the end cap form an exhaust channel with the groove, chamfer, and protrusion of the valve body. During the exhaust process, the hydraulic cylinder drives the valve stem to move axially downward relative to the valve body, reducing the cross-sectional area of ​​the exhaust channel. When the side wall of the valve stem contacts the protrusion, the exhaust channel closes. At this time, the hydraulic cylinder does not fully retract. The valve stem continues to move downward until the end cap is completely located in the receiving groove, at which point the hydraulic cylinder fully retracts.

[0008] Furthermore, the sidewall and the receiving groove are tightly fitted together.

[0009] Furthermore, the tolerance zone between the sidewall and the receiving groove is E7 / h7.

[0010] Furthermore, the groove is straight, and the width of the groove is greater than the maximum diameter of the chamfer.

[0011] Furthermore, from the groove to the through hole, the diameter of the chamfer gradually decreases.

[0012] Furthermore, the extending direction of the groove is perpendicular to the axial direction of the connecting hole.

[0013] Furthermore, the transition surface is an arc-shaped curved surface.

[0014] Furthermore, the vacuum valve also includes a guide sleeve and a first sealing ring. The guide sleeve is installed inside the valve body, and the first sealing ring is located between the guide sleeve and the valve body to seal the guide sleeve and the valve body.

[0015] Furthermore, the vacuum valve also includes a second sealing ring, which is located between the guide sleeve and the rod body, and seals the guide sleeve and the rod body.

[0016] Furthermore, the die-casting vacuum structure also includes a fixing component and a cooling component. The oil cylinder is installed on the fixing component, and the cooling component includes a cooling plate and a coolant pipe communicating with the cooling plate. The cooling plate is located on the fixing component to cool the oil cylinder.

[0017] Compared to existing technologies, the valve body of this die-cast vacuum structure has a through hole coaxially arranged with the valve stem and a connecting hole communicating with the through hole. An air extraction pipe is installed in the connecting hole. A groove is provided on the end face of the valve body away from the oil cylinder, and the through hole is located in the groove. A chamfer is provided on the top of the through hole, and the chamfer intersects with the through hole to form a convex edge. The valve body also has a receiving groove, which is coaxially arranged with the through hole. The diameter of the receiving groove is larger than the diameter of the through hole. Along the axial direction, the receiving groove is located between the groove and the connecting hole. The valve stem includes a rod body and an end cap located at the end of the rod body. The end cap includes a side wall and a transition surface, which extends from the bottom of the side wall to the end of the valve stem. The rod body portion is located within the through hole. The end cap is located on top of the valve body. The side wall and transition surface of the end cap form an exhaust channel with the groove, chamfer, and convex edge of the valve body. During the exhaust process, the hydraulic cylinder drives the valve stem to move axially downward relative to the valve body, reducing the cross-sectional area of ​​the exhaust channel. When the side wall of the valve stem contacts the convex edge, the exhaust channel is closed. At this time, the hydraulic cylinder has not fully retracted. The valve stem continues to move downward until the end cap is completely located in the receiving groove. At this time, the hydraulic cylinder fully retracts. Through the above design, when the hydraulic cylinder drives the valve stem to retract, before it has fully retracted, the valve stem and the valve body are sealed, and the exhaust channel is closed. Effective sealing is performed in advance, and the molten aluminum located above the end cap cannot enter the valve body, avoiding damage to the die-casting vacuum structure. Attached Figure Description

[0018] Figure 1 This is a perspective view of the die-casting vacuum structure of this utility model;

[0019] Figure 2 for Figure 1 A three-dimensional view of the valve stem of the die-cast vacuum structure;

[0020] Figure 3 A 3D view of a vacuum valve with a die-cast vacuum extraction structure;

[0021] Figure 4 for Figure 3 A three-dimensional sectional view of a vacuum valve;

[0022] Figure 5 for Figure 1 A cross-sectional view of the valve stem of the die-cast vacuum structure before it retracts;

[0023] Figure 6 for Figure 1 A cross-sectional view of the valve stem of the die-cast vacuum structure retracting to the point of just sealing;

[0024] Figure 7 for Figure 6 A magnified view of point A;

[0025] Figure 8 for Figure 1 A cross-sectional view of the valve stem retracting into position in the die-cast vacuum structure.

[0026] In the diagram: 10. Drive assembly; 11. Hydraulic cylinder; 12. Oil pipe; 20. Fixing assembly; 30. Cooling assembly; 31. Cooling plate; 32. Coolant pipe; 40. Valve stem; 41. Stem body; 42. End cap; 420. Side wall; 421. Transition surface; 50. Vacuum valve; 51. Valve body; 510. Connecting hole; 511. Through hole; 512. Fixing groove; 513. Groove; 514. Chamfer; 515. Raised edge; 516. Receiving groove; 52. Guide sleeve; 53. First sealing ring; 54. Second sealing ring; 55. Plug; 56. Adjusting plate; 60. Suction pipe; 70. Pressure plate. Detailed Implementation

[0027] 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.

[0028] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or it can be fixed through another intermediate component. When a component is said to be "connected to" another component, it can be directly connected to the other component or it may be fixed through another intermediate component. When a component is said to be "set on" another component, it can be set directly on the other component or it may be set through another intermediate component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0029] 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.

[0030] Please see Figures 1 to 8The die-casting vacuum structure includes a drive assembly 10, a fixing assembly 20, a cooling assembly 30, a valve stem 40, a vacuum valve 50, a vacuum pipe 60, and a pressure plate 70.

[0031] The drive assembly 10 includes a hydraulic cylinder 11 and an oil pipe 12. The oil pipe 12 is connected to the hydraulic cylinder 11, and the oil pipe 12 supplies oil to the hydraulic cylinder 11 to realize the hydraulic drive valve stem 40 to move axially.

[0032] The fixing component 20 is used to fix the drive component 10.

[0033] The cooling assembly 30 includes a cooling plate 31 and a coolant pipe 32. The cooling plate 31 has a cooling channel inside, and the coolant pipe 32 is connected to the cooling channel inside the cooling plate 31. The cooling assembly 30 cools the oil cylinder 11.

[0034] The valve stem 40 is connected to the hydraulic cylinder 11. During die casting, the hydraulic cylinder 11 drives the valve stem 40 to extend, and the end cap 42 of the valve stem 40 presses against the molten aluminum for die casting. After die casting is completed, the valve stem 40 retracts, and during the retraction process, the air in the cavity is extracted by the air extraction pipe 60. The valve stem 40 includes a stem body 41 and an end cap 42, which is fixed to the end of the stem body 41. The diameter of the end cap 42 is larger than the diameter of the stem body 41. The end cap 42 has a side wall 420 and a transition surface 421. The side wall 420 is cylindrical, and the transition surface 421 extends from the bottom of the side wall 420 to the top of the stem body 41. The transition surface 421 is curved and arc-shaped.

[0035] The vacuum valve 50 includes a valve body 51, a guide sleeve 52, a first sealing ring 53, a second sealing ring 54, a screw plug 55, and an adjusting plate 56.

[0036] The valve body 51 has a through hole 511 that penetrates the valve body 51. The rod 41 of the valve stem 40 passes through the through hole 511 and can move along the through hole 511. The top of the valve body 51 has a groove 513, which is straight. The through hole 511 is located in the groove 513, and the diameter of the through hole 511 is smaller than the width of the groove 513. The top of the through hole 511 has a chamfer 514. The top of the chamfer 514 extends to the groove 513, and the bottom of the chamfer 514 extends to the through hole 511. The diameter of the chamfer 514 gradually decreases from the groove 513 to the through hole 511. A raised edge 515 is formed at the intersection of the chamfer 514 and the through hole 511.

[0037] The valve body 51 is also provided with a receiving groove 516, which is coaxially arranged with the through hole 511. The diameter of the receiving groove 516 is larger than the diameter of the through hole 511. The receiving groove 516 is located at the top of the through hole 511 and is used to receive the retracted end cap 42.

[0038] The valve body 51 is also provided with a connection hole 510 for installing an air extraction pipe 60. The connection hole 510 is arranged radially along the valve body 51 and communicates with a through hole 511. The air extraction pipe 60 draws air through the connection hole 510, the through hole 511, and the air inlet channel. The valve body 51 is also provided with a fixing groove 512, which is located on the outer edge of the valve body 51 and is used to fix the pressure plate 70.

[0039] The guide sleeve 52 is installed inside the through hole 511, and the guide sleeve 52 and the through hole 511 are coaxially arranged. The first sealing ring 53 is installed on the outer wall of the guide sleeve 52, and the first sealing ring 53 is located between the guide sleeve 52 and the valve body 51, and the first sealing ring 53 seals the guide sleeve 52 and the valve body 51.

[0040] The second sealing ring 54 is installed on the inner wall of the guide sleeve 52, and is located between the guide sleeve 52 and the rod body 41. The screw plug 55 is installed inside the valve body 51 and is threaded into the valve body 51, so that the guide sleeve 52 is fixed to the valve body 51. The adjusting plate 56 is installed at the bottom of the valve body 51.

[0041] The air extraction pipe 60 is installed in the connection hole 510.

[0042] When using the die-casting vacuum structure, after die-casting is completed, the evacuation pipe 60 evacuates air. At this time, an evacuation channel is formed between the side wall 420 and transition surface 421 of the end cover 42 and the groove 513, chamfer 514, and protrusion 515 of the valve body 51 for evacuation. The cylinder 11 drives the valve stem 40 to move axially downward relative to the valve body 51, reducing the cross-sectional area of ​​the evacuation channel. When the side wall 420 of the valve stem 40 contacts the protrusion 515, the evacuation channel is closed. At this time, the cylinder 11 has not completely retracted. The valve stem 40 continues to move downward until the end cover 42 is completely located in the receiving groove 516. At this time, the cylinder 11 completely retracts. Through the above design, when the cylinder 11 drives the valve stem 40 to retract, before it has fully retracted, the valve stem 40 and the valve body 51 are sealed, and the evacuation channel is closed. Effective sealing is performed in advance, and the molten aluminum located above the end cover 42 cannot enter the valve body 51, avoiding damage to the die-casting vacuum structure.

[0043] The above embodiments only illustrate several implementation methods of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the utility model patent. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the concept of this utility model. These are all equivalent modifications and improvements made to the above embodiments based on the essential technology of this utility model, and all of these fall within the protection scope of this utility model.

Claims

1. A die-casting vacuum structure, comprising a drive assembly, a valve stem, a vacuum valve, and a vacuum pipe, wherein the drive assembly includes a hydraulic cylinder and an oil pipe communicating with the hydraulic cylinder, and the valve stem is throttle-connected to the hydraulic cylinder, characterized in that: The vacuum valve includes a valve body, which has a through hole coaxially arranged with the valve stem and a connecting hole communicating with the through hole. The suction pipe is installed in the connecting hole. A groove is provided on the end face of the valve body away from the hydraulic cylinder. The through hole is located in the groove. A chamfer is provided on the top of the through hole, and the chamfer intersects with the through hole to form a convex edge. The valve body also has a receiving groove, which is coaxially arranged with the through hole. The diameter of the receiving groove is larger than the diameter of the through hole. Along the axial direction, the receiving groove is located between the groove and the connecting hole. The valve stem includes a rod body and an end cap located at the end of the rod body. The end cap includes a sidewall and a transition surface. The transition surface extends from the bottom of the sidewall to the end of the valve stem. The stem portion is located in the through hole, and the end cap is located on top of the valve body. The sidewall and transition surface of the end cap form an exhaust channel with the groove, chamfer, and protrusion of the valve body. During the exhaust process, the hydraulic cylinder drives the valve stem to move axially downward relative to the valve body, reducing the cross-sectional area of ​​the exhaust channel. When the sidewall of the valve stem contacts the protrusion, the exhaust channel closes. At this time, the hydraulic cylinder does not fully retract. The valve stem continues to move downward until the end cap is completely located in the receiving groove, at which point the hydraulic cylinder fully retracts.

2. The die-casting vacuum structure according to claim 1, characterized in that: The sidewall fits tightly with the receiving groove.

3. The die-casting vacuum structure according to claim 2, characterized in that: The tolerance zone between the sidewall and the receiving groove is E7 / h7.

4. The die-casting vacuum structure according to claim 1, characterized in that: The groove is straight, and the width of the groove is greater than the maximum diameter of the chamfer.

5. The die-casting vacuum structure according to claim 4, characterized in that: From the groove to the through hole, the diameter of the chamfer gradually decreases.

6. The die-casting vacuum structure according to claim 1, characterized in that: The groove extends in a direction perpendicular to the axis of the connecting hole.

7. The die-casting vacuum structure according to claim 1, characterized in that: The transition surface is an arc-shaped curved surface.

8. The die-casting vacuum structure according to claim 1, characterized in that: The vacuum valve also includes a guide sleeve and a first sealing ring. The guide sleeve is installed inside the valve body, and the first sealing ring is located between the guide sleeve and the valve body to seal the guide sleeve and the valve body.

9. The die-casting vacuum structure according to claim 8, characterized in that: The vacuum valve also includes a second sealing ring, which is located between the guide sleeve and the rod body, and seals the guide sleeve and the rod body.

10. The die-casting vacuum structure according to claim 1, characterized in that: The die-casting vacuum structure also includes a fixing component and a cooling component. The oil cylinder is installed on the fixing component, and the cooling component includes a cooling plate and a coolant pipe communicating with the cooling plate. The cooling plate is located on the fixing component to cool the oil cylinder.

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