A high pressure die casting press

Abstract

The application provides a high-pressure die casting press, which comprises a die unit; one end of an oil cylinder is arranged at one end of the die unit to drive the die unit to move towards or away from a die casting die, and the oil cylinder is electrically connected to a hydraulic system; a shot system is connected to the other end of the die unit to press high-pressure semi-liquid metal; a main winding frame is provided with a space for mounting the oil cylinder, the shot system and the die unit; and a periphery of the main winding frame is wound with a steel wire to pre-tighten the main winding frame and make it in a compressive stress state. The application is convenient for flexible design of a column structure and a cross section, can achieve a frame support with a larger tonnage, and can meet the production requirements of super-large die castings; the oil cylinder is wound with the steel wire to offset the deformation of a movable die plate, a fixed die plate and a die during a forming and pressurizing process, reduce the size of the oil cylinder, and enhance the safety factor of the oil cylinder; an electrostatic spraying system is configured to meet the trace spraying requirements of large-size die castings; and a moving die changing platform is configured to solve the problem of difficult die changing of super-large molds.

Description

Technical Field

[0001] This invention relates to the field of high-pressure die casting, and in particular to the field of large-scale die casting parts production technology, specifically a high-pressure die casting press. Background Technology

[0002] High-pressure die casting refers to a method in which liquid or semi-liquid metal is filled into a die-casting cavity at a high speed under high pressure, and then formed and solidified under pressure to obtain a casting.

[0003] Pressure casting is characterized by two main features: high pressure and high-speed filling. It commonly uses injection pressures ranging from several thousand to tens of thousands of kPa, or even higher, with filling speeds of approximately 10-50 m / s. This results in very short filling times, typically within the range of 0.01 to 0.2 seconds. Therefore, high-pressure die casting has the following three advantages:

[0004] 1. The product is of high quality and can be manufactured in complex shapes;

[0005] 2. High production efficiency;

[0006] 3. Excellent economic results.

[0007] Larger die-cast parts will undoubtedly be a major trend in future automotive manufacturing. However, as part sizes increase, the forming process requires greater clamping force. The clamping tonnage of the largest existing die-casting machines is generally between 6,000 and 9,000 tons, which can only provide about 30 to 50 MPa of pressure for some large parts. Structural parts typically require about 70 MPa of pressure to maintain part quality. Therefore, the largest existing die-casting machines cannot meet the high-pressure requirements of large parts. Furthermore, it is difficult to make significant breakthroughs in the structure of traditional die-casting machines. Due to the characteristics of conventional materials, the larger the size of the same material, the lower the yield strength that can be achieved. Once the size reaches a certain level, it is difficult to make significant improvements. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a high-pressure die-casting press to solve the difficulties of the prior art.

[0009] To achieve the above and other related objectives, the present invention provides a high-pressure die-casting press, comprising: a mold.

[0010] unit;

[0011] The hydraulic cylinder 1 has one end abutting against one end of the mold unit and is driven to move toward or away from the die-casting mold 2, and is electrically connected to the hydraulic system 3.

[0012] The injection system 4 is connected to the other end of the mold unit to press semi-liquid metal material under high pressure. Specifically, the flowing metal is a high-temperature magnesium alloy, aluminum alloy or a composite material with the same as the main component, and the form is liquid or semi-solid.

[0013] The main winding frame 5 has a space for installing the hydraulic cylinder 1, the injection system 4 and the mold unit. The main winding frame 5 is wrapped with a No. 1 steel wire 6 around its outer periphery to pre-tighten it and put it in a compressive stress state.

[0014] According to the preferred embodiment, one or more injection systems 4 are evenly distributed on one side of the fixed template 11 to maintain the balance of the injection force borne by the press, so that the distance between the impact center calculated in terms of the off-center load and the geometric center of the template does not exceed 10% of the total dimensions of the template surface (in any direction of length or width).

[0015] According to the preferred embodiment, when there are multiple injection units for the flowing metal, the flowing metal merges at the gating structure of the mold cavity after being injected from the injection unit, and together they form the final die-cast product required. All multiple injection units are hydraulic components, and synchronous motion control of injection is achieved through a unified hydraulic real-time controller or mechanical connection mechanism.

[0016] According to a preferred embodiment, the main winding frame 5 includes a pair of parallel winding frame bodies 51 with a gap between them, and the pair of winding frame bodies 51 are connected by a column 7 and a positioning rod 8.

[0017] The two ends of the winding frame body 51 are arc-shaped, and the column 7 is arranged between the two arc-shaped ends.

[0018] According to the preferred embodiment, the winding frame body 51 is annular, including arc-shaped ends on both sides and a horizontal end in the middle;

[0019] Within the frame formed at the arc-shaped end, multiple annularly arranged reinforcing ribs 9 are connected, and the column 7 is installed through a pair of adjacent reinforcing ribs 9; the surface of the reinforcing rib 9 is tangent to the circumference of the column 7.

[0020] Multiple positioning rods 8 are installed inside the horizontal end.

[0021] According to the preferred embodiment, four sets of columns 7 are provided, which are located around the winding frame body 51 respectively, and the line connecting the four sets of columns 7 forms a rectangle.

[0022] According to the preferred embodiment, the mold unit includes:

[0023] The movable template 10 is opened and closed by a hydraulic cylinder 1 or a hydraulic cylinder 1 and a mechanical linkage or a hydraulic cylinder 1 and a follow-up locking mechanism.

[0024] Fixed template 11 is arranged parallel to moving template 10 and is installed on one end of the main winding frame 5 near the injection system 4 in the installation space.

[0025] According to the preferred embodiment, the die-casting mold 2 is transferred to the mold unit via a bottom-mounted mobile mold-changing platform 12;

[0026] An electrostatic spraying system 13 is also installed on the side near the die-casting mold 2.

[0027] According to the preferred embodiment, the outer surface of the hydraulic cylinder 1 is covered with a No. 2 steel wire 14.

[0028] According to the preferred embodiment, the corresponding hydraulic cylinder 1 is installed in the main winding frame 5 at the end of the installation space away from the injection system 4.

[0029] According to a preferred embodiment, the system also includes a part-retrieving robot 15, which is positioned near one end of the die-casting mold 2 to remove the high-pressure formed parts from the die-casting mold 2.

[0030] According to the preferred scheme, both No. 1 steel wire 6 and No. 2 steel wire 14 are made of high yield strength steel wire and high-strength linear composite materials such as carbon fiber.

[0031] This invention employs a wound frame and hydraulic cylinder structure, achieving the following beneficial effects:

[0032] (1) It facilitates flexible design of column structure and cross section, and can achieve frame support of larger tonnage (theoretically unlimited) based on the number of layers and quantity of the wound steel wire, so as to meet the production needs of ultra-large die castings.

[0033] (2) The safety factor of the spiral frame used is dozens of times that of the traditional structure;

[0034] (3) Configure a wire winding cylinder to counteract the deformation of the moving and fixed templates and molds during the forming and pressurizing process, reduce the cylinder size, and enhance the safety factor of the cylinder;

[0035] (4) Configure an electrostatic spraying system to meet the micro-spraying requirements of large die-cast parts;

[0036] (5) Configure a mobile mold changing platform to solve the problem of difficult mold changing for ultra-large molds.

[0037] The preferred embodiments of the invention will be described in more detail below with reference to the accompanying drawings, so as to facilitate an understanding of the features and advantages of the invention. Attached Figure Description

[0038] Figure 1 The diagram shown is a three-dimensional structural schematic of the present invention.

[0039] Figure 2 This is a three-dimensional structural schematic diagram showing another perspective of the present invention;

[0040] Label Explanation

[0041] 1. Hydraulic cylinder; 2. Die-casting mold; 3. Hydraulic system; 4. Injection system; 5. Main winding frame; 6. No. 1 steel wire; 7. Column; 8. Positioning rod; 9. Reinforcing rib; 10. Moving template; 11. Fixed template; 12. Moving mold changing platform; 13. Electrostatic spraying system; 14. No. 2 steel wire; 15. Parts picking robot. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0043] Compared to the embodiments shown in the accompanying drawings, feasible embodiments within the scope of protection of this invention may have fewer components, other components not shown in the drawings, different components, components arranged differently, or components with different connections, etc. Furthermore, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as multiple separate components.

[0044] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, “an” or “a” and similar terms do not necessarily indicate a quantity limitation. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0045] This invention proposes a high-pressure die-casting press for manufacturing large-scale die-cast parts. While not limiting the type of large-scale die-cast parts, this invention breaks away from the traditional approach of continuously increasing the diameter of the tie rods and the yield strength of the material to achieve a large-tonnage die-casting frame structure. It introduces the concept of a wire-wound frame, which significantly improves the rigidity of the four columns, the load-bearing area, and the overall frame strength, while also providing a high safety factor. This enhances the limits achievable by large-tonnage die-casting presses, enabling the creation of even larger-tonnage die-casting presses.

[0046] In general, the high-pressure die-casting press proposed in this invention mainly includes a mold unit, a hydraulic cylinder 1, an injection system 4, and a main winding frame 5. See also... Figure 1 It shows the arrangement of the mold unit, the hydraulic cylinder 1, the injection system 4 and the main winding frame 5.

[0047] As mentioned above, the concept of a wire-wound frame is introduced. The wire is made of high-yield-strength steel with a yield strength of 1300-1600 MPa. The main frame is adapted to be a main-wound frame 5. The main-wound frame 5 is arranged as a pair of parallel and spaced-apart winding frame bodies 51. The outer periphery of the winding frame body 51 is wrapped with No. 1 steel wire 6. The steel wire is wound around the dynamic / static bottom surface of the press frame under high tension. After winding, the pre-tightening stress of the steel wire is about 650 MPa, and the total pre-tightening force is 1.05 to 1.1 times the maximum working force of the equipment.

[0048] In addition, during the implementation process, except for the area on the worktable where there is flowing metal injection, the frame in other areas is wrapped with high-tension pre-tightened steel wire, covering an area of ​​30-80% of the overall worktable area.

[0049] The thickness of the wire winding is related to the rated pressure of the press and the size of the worktable to ensure that the elastic deformation of the worktable does not exceed 0.2mm and the deflection of the press worktable is less than 1 / 10000 under the casting pressure with an average pressure not exceeding 100Mpa.

[0050] The total length of the steel wire used for winding depends on the configuration of the press worktable, and the dimensions of the moving / static templates depend on the dimensions of the die-casting product. Generally, the dimension in a single direction (length or width) is 1000-6500mm.

[0051] The winding frame body 51 has a ring frame structure, with a space for installing the oil cylinder 1, the injection system 4 and the mold unit. The outer ring frame includes arc-shaped ends on both sides and a horizontal end in the middle. The frame formed by the arc-shaped ends is connected by multiple ring-arranged reinforcing ribs 9. The column 7 passes through a pair of adjacent reinforcing ribs 9 to install a pair of winding frame bodies 51. Multiple positioning rods 8 are installed in the horizontal end. Preferably, there are four sets of columns 7, which are located around the winding frame body 51 respectively. The line connecting the four sets of columns 7 is rectangular.

[0052] It needs to be specifically explained that the No. 1 steel wire 6 is wrapped around the main winding frame 5. The main winding frame 5 is pre-tightened by the high yield strength steel wire. The surface of the reinforcing rib 9 is tangent to the circumference of the column 7, so that the column 7 is always under compressive stress. Therefore, the requirements for the yield strength (200~500Mpa) of the column 7 material are not high, which is conducive to more flexible design of the column structure and cross-sectional area. There are few restrictions. During operation, the high yield strength steel wire (1300~1600Mpa) is used to bear the working pressure, which can meet the requirements of higher tonnage bearing capacity.

[0053] As mentioned above, the main winding frame 5 houses the space for the hydraulic cylinder 1, the injection system 4, and the mold unit. Specifically, the mold unit contains a pair of parallel fixed templates 11 and movable templates 10. The fixed templates 11 are installed at the end of the installation space within the main winding frame 5 closest to the injection system 4. The movable templates 10 are connected to the hydraulic cylinders 1 driven by the hydraulic system 3. High-pressure hydraulic cylinders are evenly distributed on one side of the movable templates 10, providing clamping force during the mold closing (injection and pressure holding) phase. The working pressure of the hydraulic cylinders is 15-200 MPa. Furthermore, the hydraulic cylinders 1 are installed at the end of the installation space within the main winding frame 5 furthest from the injection system 4. Further, the movable templates 10 can be secured by three mechanisms: hydraulic cylinder 1, hydraulic cylinder 1 and a mechanical linkage, or hydraulic cylinder 1 and a follow-up locking mechanism.

[0054] The system enables opening and closing, and the moving template allows for rapid movement at speeds of 0-1000 mm / s and strokes of 800-3000 mm. Specifically:

[0055] When the moving template 10 is completely opened and closed and locked by the hydraulic cylinder, it can be achieved by a high-pressure hydraulic cylinder, or a conventional hydraulic cylinder that only works at pressure below 30 MPa can be added in addition to the high-pressure hydraulic cylinder to jointly realize the function of moving the moving template and locking the mold.

[0056] When the moving template 10 is opened, moved and locked by the combined action of the hydraulic cylinder and the mechanical linkage, the driving hydraulic cylinder is located on the frame connecting block, and the driving mechanical linkage structure drives the moving template to achieve rapid mold closing and locking;

[0057] When the moving template 10 is opened and moved and locked by the opening and closing cylinder and the follow-up locking mechanism, the following locking mechanism includes a split nut and a locking cylinder. The split nut can be opened and closed. When closed, it engages with the clamping tooth groove on the column. When opened, it disengages. The locking cylinder is a thin hydraulic chamber used to stretch the column and lock the mold. The opening and closing cylinder is located at the rear end of the moving template and completes the opening and closing action.

[0058] In this preferred embodiment, the die-casting mold 2 is horizontally transferred to the mold unit by the movable mold-changing platform 12 located at the bottom, which reduces the workload, reduces the alignment time, improves the work efficiency, and avoids the problem of difficult mold changing for ultra-large molds. In addition, an electrostatic spraying system 13 is installed on the side near the die-casting mold 2, which can meet the micro-spraying requirements of large die-casting parts.

[0059] It needs to be specifically explained that the hydraulic cylinder 1 has a No. 2 steel wire 14 wrapped around its outer surface. The No. 2 steel wire 14 is made of high yield strength steel wire or high-strength linear composite material such as carbon fiber. The No. 2 steel wire 14 is used to achieve local pressure increase of the hydraulic cylinder 1. The use of a wound hydraulic cylinder can greatly reduce the size of the cylinder body and greatly enhance the safety factor of the hydraulic cylinder. It can also increase the driving pressure of the hydraulic cylinder and directly provide the mold closing force, which is more conducive to counteracting the deformation of the moving and fixed templates and the mold during the forming pressure increase process.

[0060] During operation, the wire winding cylinder 1 operates in two stages: a normal pressure condition and a boosted high pressure condition. The normal pressure condition is during the rapid oil movement in and out stage, with a working pressure of 0-25 MPa. The boosted high pressure condition is during the stage from rest to the mold closing position and the establishment of the clamping force, with a working pressure of 25-200 MPa achieved through a high pressure booster.

[0061] like Figure 1 As shown, the die-casting machine has a maximum clamping force of 20,000T, and the wire winding preload is 1.05 to 1.1 times the maximum working pressure. The design value is 22,000T to provide the load-bearing capacity of the press frame. Five winding cylinders provide the clamping force, each with a force of 4,000T. The cylinders employ a localized increase system, with a maximum working pressure of 100 MPa and a cylinder stroke of 2,500 mm. The dimensions of the moving and fixed mold plates are as follows.

[0062] The 4000mm*4000mm size meets the production requirements for 1500*1700*900 die-cast parts. Finally, the high-pressure formed parts are removed from the die-casting mold 2 using the part removal tool 15.

[0063] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A high-pressure die-casting press, characterized in that, include: Mold unit; The cylinder (1) has one end abutting against one end of the mold unit and is driven to move toward or away from the die-casting mold (2), and is electrically connected to the hydraulic system (3); The injection system (4) is connected to the other end of the mold unit to press semi-liquid metal material under high pressure; The main winding frame (5) has a space for installing the oil cylinder (1), the injection system (4) and the mold unit. The main winding frame (5) is wrapped with a No. 1 steel wire (6) around its outer periphery to pre-tighten the main winding frame (5) so that it is under compressive stress.

2. The high pressure die casting press of claim 1, wherein, The main winding frame (5) includes a pair of parallel winding frame bodies (51) with a gap between them, and the pair of winding frame bodies (51) are connected by a column (7) and a positioning rod (8). The two ends of the winding frame body (51) are arc-shaped, and the column (7) is set between the two arc-shaped ends.

3. The high-pressure die-casting press according to claim 2, characterized in that, The winding frame body (51) is ring-shaped, including arc-shaped ends on both sides and a horizontal end in the middle; Within the frame formed at the arc-shaped end, multiple annularly arranged reinforcing ribs (9) are connected, and the column (7) is installed through a pair of adjacent reinforcing ribs (9); the surface of the reinforcing ribs (9) is tangent to the circumference of the column (7); Multiple positioning rods (8) are installed inside the horizontal end.

4. The high-pressure die-casting press according to claim 3, characterized in that, The mold unit includes: The movable template (10) is opened and closed by a hydraulic cylinder (1) or a hydraulic cylinder (1) and a mechanical linkage or a hydraulic cylinder (1) and a follow-up locking mechanism; Fixed template (11) is set parallel to moving template (10). Fixed template (11) is installed in the main winding frame (5) at one end of the installation space near the injection system (4).

5. The high-pressure die-casting press according to claim 4, characterized in that, The die-casting mold (2) is transferred to the mold unit via a movable mold-changing platform (12) with its bottom set; An electrostatic spraying system (13) is also installed on the side near the die-casting mold (2).

6. The high-pressure die-casting press according to claim 5, characterized in that, The outer surface of the oil cylinder (1) is covered with No. 2 steel wire (14).

7. The high-pressure die-casting press according to claim 6, characterized in that, It also includes a part-retrieving robot (15), which is positioned near one end of the die-casting mold (2) to remove the high-pressure formed parts from the die-casting mold (2).

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