Adjustable oil press lower die

Abstract

This invention discloses an adjustable lower die for a hydraulic press, belonging to the field of metal sheet forming and processing technology. The lower die includes at least one lower die unit, each unit comprising a bottom support frame and two support plates symmetrically arranged and hinged to each other. Slide rails are provided on both sides of the two support plates, with a first slider installed within each slide rail. At least one first support rod is hinged to each support plate, with the other end of the first support rod hinged to the first slider. An angle adjustment block can also be detachably installed within the slide rail, with one end abutting against the slide rail end cover and the other end abutting against the first slider. By replacing angle adjustment blocks of different lengths, the position of the first slider within the slide rail can be precisely adjusted, thereby changing the included angle between the two support plates and achieving rapid and precise adjustment of the die's working angle. Extended connecting pieces are provided at both ends of the bottom support frame for the lateral splicing of multiple lower die units to adapt to the processing requirements of sheets of different lengths.

Description

Technical Field

[0001] This invention relates to the field of metal sheet forming and processing technology, and specifically to an adjustable hydraulic press lower mold. Background Technology

[0002] In the field of sheet metal forming and processing, especially in industries such as shipbuilding and large container manufacturing, it is often necessary to bend large sheets with significant thickness and length. As a core processing equipment, the structure and performance of the lower die of a hydraulic press directly determine the accuracy, efficiency, and applicability of bending and forming.

[0003] Traditional hydraulic presses typically use fixed-structure dies, meaning the angle and depth of their V-shaped or U-shaped working surfaces are constant. This type of fixed die has several significant drawbacks: First, due to variations in the material, thickness, and required bending angle of the sheet metal, frequent changes of dies with different angles are necessary. This not only increases die inventory costs but also significantly reduces production efficiency. Die-changing often requires multiple people working together, making it time-consuming and labor-intensive. Second, for applications like shipyards that require processing extra-long sheet metal, traditional integral long dies are difficult and costly to manufacture, and their immense weight makes hoisting and installation extremely inconvenient. Third, when the lateral span during bending needs to be adjusted to accommodate workpieces of different shapes, traditional dies lack a flexible height adjustment mechanism, often requiring the addition of shims or replacement of the entire die set, resulting in cumbersome operations and difficulty in guaranteeing accuracy. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects in the prior art and provide an adjustable hydraulic press lower mold.

[0005] To achieve the above objectives, the technical solution of the present invention is to design an adjustable hydraulic press lower mold, including at least one lower mold unit. The lower mold unit includes a bottom support frame and two support plates that are symmetrically arranged on the bottom support frame and hinged to each other. Multiple slide rails are provided on both sides of the two support plates. A first slider is installed in the slide rail. At least one first support rod is hinged to the support plate. The other end of the first support rod is hinged to the first slider. An angle adjustment block can also be detachably installed in the slide rail. One end of the angle adjustment block abuts against the end cover of the slide rail, and the other end abuts against the first slider. Extension connecting pieces are provided at both ends of the bottom support frame.

[0006] By setting two hinged support plates, the angle of the left and right support plates can be changed. A rigidly adjustable support mechanism is formed by setting a slide rail, a first slider, a first support rod, and a detachable angle adjustment block. The length of the angle adjustment block determines the fixed position of the first slider within the slide rail, and the first support rod precisely controls the angle between the two support plates. Furthermore, the first support rod also provides support, improving the overall load-bearing capacity of the mold. The extended connector is preferably a bolt or other quick-release connector, which can stably splice multiple lower mold units along a straight line to form a long mold with unlimited expandable length, solving the problem of insufficient mold length in the processing of large sheet metal. The bottom support frame provides a stable foundation for the entire unit, ensuring structural rigidity under heavy-load bending conditions.

[0007] Optionally, the two support plates are hinged at their bottoms by a first hinge and a second hinge, forming a V-shape. The first hinge is located on the bottom of the two support plates, and the second hinge is located in the middle of the bottom support frame. This technical solution provides a first specific hinge method for the support plates, where the bottoms of the two support plates are respectively hinged to a second hinge (preferably a hinge shaft or a semi-circular hinge slot, with the hinge shafts or hinge slots on the left and right support plates staggered) and a common hinge axis, allowing the two support plates to rotate around a common hinge axis, forming a V-shaped structure. The advantages of this hinge method are its simple structure, high support stability, fixed rotation center of the two support plates, easy precise control of their included angle through a linkage mechanism, and clear force transmission path, which helps to ensure the overall rigidity of the mold.

[0008] Optionally, the two support plates are hinged near the bottom by a third hinge and a fourth hinge, forming an X-shape. The third hinge is located near the bottom of the two support plates, and the fourth hinge is a hinge shaft. A second slider is hinged to the bottom of each support plate, and the second slider slides in cooperation with a slide rail. This technical solution provides a second specific hinge method for the support plates, where the two support plates are cross-hinged in the middle by a third hinge (preferably a hinge cylinder) and a fourth hinge (preferably a hinge shaft, cooperating with the hinge cylinder), forming an X-shaped structure. The bottom of each support plate can slide within the slide rail of the bottom support frame via the second slider. The advantage of this X-shaped hinge structure is that changing the included angle between the two support plates changes the height of the top working surface, and the bottom can also provide effective support, resulting in a stable overall structure.

[0009] Preferably, the distance between the hinge point of the first support rod and the support plate and the hinge point of the first support rod and the first slider is L1, and the distance between the hinge point of the first support rod and the support plate and the hinge point of the first hinge member and the second hinge member, or the distance between the hinge point of the first support rod and the support plate and the second slider, is L2, where L1=L2. In this case, the length of the angle adjustment block is L3=D-2×L1×cos(90°-θ / 2); where D is the distance between the contact end of the slide rail and the angle adjustment block and the hinge point of the first hinge member and the second hinge member, and θ is the included angle between the left and right support plates.

[0010] This technical solution defines the geometric parameter relationships of the first support rod and other components. By setting L1 equal to L2, the first support rod, the slide rail section containing the first slider, and the lines connecting the hinge points on the support plate to the other hinge point form an equilateral triangle structure. Under this geometric relationship, there is a certain functional relationship between the length L3 of the angle adjustment block and the required angle θ. Through this functional relationship, the operator can pre-calculate or directly select or manufacture the corresponding angle adjustment block according to the scale markings, thus ensuring the accuracy and repeatability of angle adjustment, avoiding errors caused by experience-based adjustments, and ensuring the stability of bending processing quality. The D value, as a basic dimension, is a fixed value once the mold structure is determined.

[0011] Specifically, the support plate includes a main support plate and a top support plate. The main support plate is located below the top support plate, and the two are connected by a heightening connector. The two main support plates are hinged together, and the upper end of the top support plate has an arc-shaped surface. The support plate is designed as a combinable, modular structure. The main support plate serves as the basic load-bearing component, while the top support plate serves as the working component that directly contacts the sheet metal. The two are connected by a heightening connector (preferably bolts or other fastening structures). The arc-shaped surface design at the upper end of the top support plate effectively reduces friction and scratches between the sheet metal and the mold edge during bending, protecting the surface quality of the sheet metal.

[0012] Furthermore, the support plate also includes an extension support plate, which is located between the main support plate and the top support plate and connected by heightening connectors. By adding one or more extension support plates between the main support plate and the top support plate, a wider range and more levels of adjustment of the total height of the support plate can be achieved. This makes the lateral span adjustment of the mold more flexible and precise.

[0013] Preferably, the hinge point between the first support rod and the support plate is located at the splicing point of two adjacent main support plates, extension support plates, and top support plates. Positioning the hinge point between the first support rod and the support plate at the splicing point of the support plate modules allows the supporting force of the first support rod to act directly on the module connection, helping to counteract the tendency of module separation caused by bending forces and enhancing the connection stability of the combined support plate structure.

[0014] Preferably, the angle adjustment block includes a fixed-length block and a movable-length block. The angle adjustment block is designed as a combination of fixed-length and movable-length blocks, so that the total length of the angle adjustment block is no longer a single fixed value, but can be adjusted as needed. The fixed-length blocks can be a series of blocks with standard lengths, such as 10 mm, 20 mm, 50 mm, etc., while the movable-length blocks can be fine-tuning blocks, such as thin sheets with thicknesses of 1 mm, 2 mm, 5 mm, or telescopic blocks with threaded adjustment functions. By combining the fixed-length block with one or more movable-length blocks, the required L3 length value can be precisely assembled, thereby achieving stepless or quasi-stepless adjustment of the mold angle. This avoids manufacturing a separate integral angle adjustment block for each angle, greatly reducing the number and types of spare parts required, lowering costs, and improving the precision and flexibility of angle adjustment. Operators can quickly select the corresponding fixed and movable blocks from the standard parts library for assembly based on the calculated L3 value.

[0015] Furthermore, the slide rail is equipped with corresponding angle markings. These intuitive markings make angle adjustment more convenient and visual. The markings can be angle values ​​directly engraved on the side of the slide rail, such as 30°, 45°, and 60°. These angle values ​​correspond to the angle between the two support plates when the first slider is in a specific position. When adjusting the angle, the operator does not need to perform complex measurements and calculations; they simply move the first slider to the mark corresponding to the target angle and then install the matching angle adjustment block.

[0016] The advantages and beneficial effects of this invention are as follows: The angle adjustment block, slider, and support rod enable rapid and precise adjustment of the mold's working angle. Operators only need to replace angle adjustment blocks of different lengths to accurately lock the required angle. Furthermore, the support plate, support rod, slider, and angle adjustment block form a stable triangular support structure capable of withstanding greater downward pressure. By setting extended connecting parts, multiple independent lower mold units can be freely spliced, allowing the total length of the lower mold to be infinitely extended according to the length of the sheet material to be processed. This modular design greatly reduces the manufacturing, transportation, and installation difficulty of ultra-long molds, making it particularly suitable for scenarios such as shipyards that require processing sheets several meters or even tens of meters long, significantly improving the flexibility of the production line. By designing the support plate as a stackable modular structure (main support plate, extension support plate, top support plate), multi-level adjustment of the mold's lateral span is achieved. Users can flexibly adjust the mold opening depth and height according to the sheet thickness, bending radius, and equipment capacity. One mold can cover the processing needs of various sheet specifications, significantly reducing mold procurement and inventory costs. The adjustment mechanism of this invention is entirely mechanical, employing high-strength sliders, slide rails, and support rods, without hydraulic or pneumatic components. It possesses extremely high load-bearing capacity and impact resistance, capable of handling heavy-duty bending tasks on thick and high-strength plates. The rational design of each connection point and clear force transmission path ensure structural stability and long-term reliability under enormous bending forces. The entire adjustment process requires no complex tools or specialized skills; ordinary operators can complete it independently based on the scale markings on the slide rails. Attached Figure Description

[0017] Figure 1 This is a top view of the mold of the present invention; Figure 2 This is a left view of the mold of the present invention; Figure 3 This is a schematic diagram of the V-shaped structure support plate of the present invention; Figure 4 This is a schematic diagram of the X-shaped structure support plate of the present invention; Figure 5 This is a schematic diagram of the angle adjustment block structure of the present invention.

[0018] In the diagram: 1. Bottom support frame; 2. Slide rail; 3. First slider; 4. First support rod; 5. Angle adjustment block; 501. Fixed length block; 502. Movable length block; 6. Extended connector; 711. First hinge; 712. Second hinge; 721. Third hinge; 722. Fourth hinge; 723. Second slider; 801. Main support plate; 802. Top support plate; 803. Extension support plate; 804. Heightening connector; 805. Curved surface. Detailed Implementation

[0019] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0020] according to Figure 1 As shown, the present invention is an adjustable lower die for a hydraulic press, comprising multiple lower die units arranged in a straight line and interconnected to form the required working length. For ease of explanation, this embodiment uses one lower die unit as an example for structural description.

[0021] according to Figure 1 As shown, the lower mold unit mainly includes a bottom support frame 1, two symmetrically arranged support plates, and an angle adjustment mechanism. The bottom support frame 1 is welded from high-strength steel plates and has a long, box-shaped structure with sufficient rigidity and strength to withstand bending pressure. Extended connecting parts 6 are fixedly installed at both ends of the bottom support frame 1. These extended connecting parts 6 can be connecting plates with bolt holes or matching boss and groove structures. When multiple units need to be assembled, the extended connecting parts 6 of adjacent units are fastened together with high-strength bolts to form a single long mold.

[0022] according to Figure 2 , 3 As shown, the two support plates in this embodiment have a V-shaped structure, and their bottoms are hinged to the bottom support frame 1 via a first hinge 711 and a second hinge 712. Specifically, each support plate has an ear plate welded to its inner bottom side. This ear plate is hinged to the first hinge 711 (e.g., a lubricated pin) and the second hinge 712 (e.g., a semi-circular bushing of the same length as the unit) via a first hinge 711. The pin is arranged at multiple intervals. The second hinge 712 is welded or bolted to the middle position of the bottom support frame 1. With this hinge structure, the two support plates can rotate around the same horizontal axis, forming a V-shaped structure. The opposing inner surfaces of the two support plates serve as the main support surfaces when the sheet metal is bent, and their surfaces are hardened to improve wear resistance.

[0023] according to Figure 3 As shown, multiple slide rails 2 are fixedly installed on both sides of the two support plates, that is, on the left and right sides of the bottom support frame 1, respectively, by bolts or welding. (The multiple slide rails 2 are arranged side by side, and the length direction of the slide rails 2 is perpendicular to the length direction of the lower mold unit). The slide rails 2 are U-shaped or other shapes. A first slider 3 is slidably installed inside each slide rail 2. The mating surface between the first slider 3 and the slide rail 2 is precision machined to ensure smooth sliding and minimal gaps. On the outer surface of each support plate, multiple first support rods 4 are hinged to each other via hinge seats. The other end of each first support rod 4 is hinged to a corresponding first slider 3 via another hinge seat. The length of the first support rod 4 is fixed.

[0024] according to Figure 1 As shown, inside the slide rail 2, between the end cap (away from the middle support plate) and the first slider 3, an angle adjustment block 5 is detachably installed. One end of the angle adjustment block 5 abuts against the inner side of the closed end cap of the slide rail 2, and the other end abuts against the side of the first slider 3 facing the end cap. The length L3 of the angle adjustment block 5 determines the final fixed position of the first slider 3 within the slide rail 2. When the first slider 3 is held in place by the angle adjustment block 5 and cannot move towards the end cap, its position is locked. Since one end of the first support rod 4 is hinged to the support plate and the other end is hinged to the first slider 3, the position of the first slider 3 is fixed by locking the angle of the support plate through the first support rod 4. Therefore, by replacing angle adjustment blocks 5 of different lengths, the included angle θ between the two support plates can be precisely adjusted and locked.

[0025] In this embodiment, the side of the slide rail 2 is clearly laser-etched with scale markings corresponding to the angles, for example, from 30° to 120°, with each scale marking every 5°. The operator simply moves the first slider 3 to the corresponding scale position according to the desired bending angle, then inserts the angle adjustment block 5 (calculated or obtained from a table) into the gap between the end cap of the slide rail 2 and the first slider 3, and locks the end cap to complete the angle adjustment. To enhance the load-bearing capacity of the end cap, a rigid support plate can be provided on the outside of the end cap for auxiliary support. The angle adjustment block 5 can also be placed directly inside the slide rail 2 without removing the end cap. When using this method, to prevent the angle adjustment block 5 from being accidentally squeezed out, bolts or clamps can be used for reinforcement.

[0026] according to Figure 2 , 3 As shown, to meet the bending requirements of different heights (i.e., different lateral spans), the support plate in this embodiment adopts a modular design. The support plate includes a main support plate 801 located below and a top support plate 802 located above. The main support plates 801 are hinged together to form a basic support. The top support plate 802 is connected to the main support plate 801 through a heightening connector 804. The heightening connector 804 can be a connecting plate with bolt holes, and the operator can fasten the two together with high-strength bolts to form a rigid connection. The upper end face of the top support plate 802 is machined into a smooth arc surface 805. The radius of this arc surface 805 is designed according to the commonly used plate thickness to reduce friction marks on the plate surface during bending.

[0027] according to Figure 2 , 3As shown, in another embodiment, the modular structure of the support plate is further optimized to enhance its adaptability. In addition to the main support plate 801 and the top support plate 802, the support plate also includes at least one extension support plate 803. The extension support plate 803 is located between the main support plate 801 and the top support plate 802. The three are securely connected by multiple heightening connectors 804. The heightening connectors 804 can be threaded positioning sleeves with internal threads and high-strength bolts inserted into them. For example, the upper end face of the main support plate 801 has multiple positioning pin holes and threaded blind holes; the lower end face of the extension support plate 803 has corresponding positioning pins and through holes, and its upper end face also has positioning pin holes and threaded blind holes; the lower end face of the top support plate 802 has corresponding positioning pins and through holes. During assembly, the precise position between the plates is first ensured by the positioning pins, and then the bolts are screwed into the threaded blind holes below through the through holes to achieve a tight connection. The extension support plate 803 can be designed with various standard heights, greatly expanding the mold's process range.

[0028] The hinge point between the first support rod 4 and the support plate is specifically set at the splicing plane between the main support plate 801 and the top support plate 802. In this way, the first support rod 4 can bear the load at the connection point, thereby preventing the connection point from breaking when subjected to large downward pressure.

[0029] like Figure 4 As shown, this embodiment provides two support plates with an X-shaped structure. Similar to the V-shaped structure, this embodiment also includes a bottom support frame 1, a slide rail 2, a first slider 3, a first support rod 4, an angle adjustment block 5, and an extended connecting piece 6, among other basic structures. The difference lies in the connection method of the two support plates. In this embodiment, the two support plates are hinged to each other near the bottom by a third hinge 721 and a fourth hinge 722, forming an overall X-shaped cross structure. Specifically, each support plate has a hinge hole near the middle of its body, and a long hinge shaft, serving as the fourth hinge 722, passes through the hinge holes of both support plates simultaneously, forming a scissor-like connection. At the bottom of each support plate, instead of being connected to the bottom support frame 1 by a fixed hinge seat, a second slider 723 is hinged. This second slider 723 slides in engagement with the slide rail 2 located on the upper surface of the bottom support frame 1. This slide rail 2 can be part of the same group as the slide rail 2 used for angle adjustment, or it can be a separate group of slide rails independently located at the bottom. When the angle of the two support plates changes, their bottoms will move closer or further apart, thereby causing the second slider 723 to slide within the bottom slide rail 2.

[0030] according to Figure 2 , Figure 5As shown, to achieve precise adjustment, this embodiment defines the distance from the hinge point between the first support rod 4 and the support plate to the hinge point between the first support rod 4 and the first slider 3 as L1. The distance from the hinge point between the first support rod 4 and the support plate to the hinge point of the second slider 723 is defined as L2. Through design, L1 is made equal to L2. Simultaneously, the horizontal distance from the end face of the end cap where the slide rail 2 abuts against the angle adjustment block 5 to the hinge point of the second slider 723 (i.e., the bottom fulcrum of the support plate) is defined as D. When it is necessary to set the included angle of the support plate to θ, the required length L3 of the angle adjustment block 5 can be precisely calculated using the formula L3=D-2×L1×cos(90°-θ / 2). Based on the calculation results, the operator combines the fixed length block 501 and the movable length block 502 in the angle adjustment block 5 to assemble the required L3 value. The fixed length block 501 is a series of metal blocks of standard length (such as 10mm, 20mm, 50mm), and the movable length block 502 is a thin sheet with a thickness of 1mm, 2mm, 5mm. By combining them, fine adjustment can be achieved in 1mm increments.

[0031] In all embodiments, the sliding components such as the slide rail 2, the first slider 3, and the second slider 723 are made of wear-resistant materials and are equipped with lubrication structures (such as oil grooves and oil nozzles) to ensure flexibility and accuracy during long-term use. The first support rod 4 is made of high-strength alloy steel, and its hinge points at both ends are equipped with spherical bearings to accommodate the slight wobble caused by changes in the angle of the support plate.

[0032] The work process is as follows: When it is necessary to bend a batch of 20mm thick steel plates at 90°, the operation process is as follows: Length splicing: Calculate the required number of lower mold units based on the length of the steel plate (e.g., 6 meters). Connect the corresponding number of lower mold units sequentially with bolts using extension connectors 6 to form a lower mold with a total length of 6 meters (slightly larger or smaller is acceptable, depending on the actual working conditions).

[0033] Height adjustment: Determine the required lateral span according to process requirements. If the span needs to be increased, add an appropriate number of extension support plates 803 between the main support plate 801 and the top support plate 802, and tighten them with bolts.

[0034] Angle Adjustment: Refer to the process card to determine that the required mold angle is 90°. Observe the scale markings on slide rail 2 and move the first slider 3 to the position marked "90°" on slide rail 2. Then, retrieve the pre-manufactured angle adjustment block 5 of length L3 corresponding to this position from the spare parts warehouse (or calculate and combine the fixed length block 501 and the movable length block 502 according to the formula to make L3 meet the calculation result). Place the angle adjustment block 5 between the end cap of slide rail 2 and the first slider 3, so that the first slider 3 is firmly held in place.

[0035] Processing begins: Start the hydraulic press, the upper mold descends, pressing the steel plate into the V-shaped opening of the lower mold, completing a 90° bend. Because the top support plate 802 has an arc-shaped surface 805 at its upper end, there are no obvious indentations on the surface of the steel plate after bending.

[0036] Task Change: When a steel plate needs to be bent at a 45° angle, simply remove the original angle adjustment block 5, move the first slider 3 to the "45°" mark, replace it with the angle adjustment block 5 of the corresponding length and lock it in place, and a new round of processing can begin. The entire process requires no hoisting or replacement of the entire mold set and can be completed within minutes.

[0037] In summary, this invention, through its unitization, modularization, and unique mechanical locking and adjustment structure, provides a highly flexible, precise, reliable, and cost-effective solution for bending large sheet metal, and has extremely high industrial application value.

[0038] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An adjustable oil press lower die, characterized by, The device includes at least one lower mold unit, which includes a bottom support frame (1) and two support plates that are symmetrically arranged on the bottom support frame (1) and hinged to each other. Multiple slide rails (2) are provided on both sides of the two support plates. A first slider (3) is installed in the slide rail (2). At least one first support rod (4) is hinged on the support plate. The other end of the first support rod (4) is hinged to the first slider (3). An angle adjustment block (5) can also be detachably installed in the slide rail (2). One end of the angle adjustment block (5) abuts against the end cap of the slide rail (2) and the other end abuts against the first slider (3). Both ends of the bottom support frame (1) are provided with extension connectors (6).

2. An adjustable oil press lower die according to claim 1, characterized in that The two support plates are hinged at the bottom by a first hinge (711) and a second hinge (712), forming a V-shape. The first hinge (711) is located on the bottom of the two support plates, and the second hinge (712) is located in the middle of the bottom support frame (1).

3. The adjustable hydraulic press lower mold according to claim 1, characterized in that, The two support plates are hinged near the bottom by a third hinge (721) and a fourth hinge (722), forming an X shape. The third hinge (721) is located near the bottom of the two support plates, and the fourth hinge (722) is a hinge shaft. A second slider (723) is hinged to the bottom of the support plate, and the second slider (723) slides in cooperation with the slide rail (2).

4. An adjustable hydraulic press lower mold according to claim 2 or 3, characterized in that, The distance between the hinge point of the first support rod (4) and the support plate and the hinge point of the first support rod (4) and the first slider (3) is L1. The distance between the hinge point of the first support rod (4) and the support plate and the hinge point of the first hinge member (711) and the second hinge member (712) or the distance between the hinge point of the first support rod (4) and the support plate and the second slider (723) is L2, where L1=L2. At this time, the length of the angle adjustment block (5) is L3=D-2×L1×cos(90°-θ / 2) Where D is the distance between the contact end of the slide rail (2) and the angle adjustment block (5) and the hinge point of the first hinge (711) and the second hinge (712), and θ is the included angle between the left and right support plates.

5. The adjustable hydraulic press lower mold according to claim 1, characterized in that, The support plate includes a main support plate (801) and a top support plate (802). The main support plate (801) is located below the top support plate (802). The two are connected by a heightening connector (804). The two main support plates (801) are hinged to each other. The top support plate (802) has an arc-shaped surface (805) at its upper end.

6. An adjustable hydraulic press lower mold according to claim 5, characterized in that, The support plate also includes an extension support plate (803), which is located between the main support plate (801) and the top support plate (802) and is connected by a heightening connector (804).

7. The adjustable hydraulic press lower mold according to claim 1, characterized in that, The hinge point between the first support rod (4) and the support plate is located at the splicing point of two adjacent main support plates (801), extension support plates (803), and top support plates (802).

8. An adjustable hydraulic press lower mold according to claim 1, characterized in that, The angle adjustment block (5) includes a fixed length block (501) and a movable length block (502).

9. An adjustable hydraulic press lower mold according to claim 1, characterized in that, The slide rail (2) is provided with scale markings corresponding to the angles.

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