Graded continuous pressurization system

Abstract

The invention relates to the technical field of hydraulic systems, and discloses a graded continuous pressurization system which comprises a working oil cylinder and a control device and further comprises a pressurization cylinder set, the pressurization cylinder set comprises at least two pressurization oil cylinders connected in parallel and a reversing mechanism, and all the pressurization oil cylinders alternately pressurize the working oil cylinder through the reversing mechanism; the number of the pressure cylinder sets is two or more, and the pressure cylinder sets have different pressure ratios. The number of the pressure sources is more than two, and one pressure source is shared by one pressurizing oil cylinder of each pressurizing cylinder group; a monitoring mechanism; the control device selects the pressurizing cylinder sets with different pressurizing ratios to pressurize the working oil cylinders and meanwhile controls the reversing mechanisms of the pressurizing cylinder sets in the same set to pressurize the working oil cylinders alternately. The multiple sets of pressurizing cylinders with different pressurizing ratios work alternately, pressure source configuration is optimized, high-pressure continuous output is achieved, pressurizing efficiency is improved, and the system structure is simplified.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system technology, and in particular to a graded continuous pressurization system. Background Technology

[0002] With industrial development and advancements in materials technology, energy conservation and emission reduction are among the current development goals. Inevitably, high-strength lightweight alloys are widely used in various industrial sectors, such as automobiles and aerospace. The practical application of these high-strength lightweight alloy materials relies heavily on forging and die-forging or extrusion processes, such as those used in 5-series and 7-series high-strength aluminum alloys. During this process, the material grains are elongated along the extrusion direction, forming a fibrous structure that improves the material's strength and toughness.

[0003] The following requirements apply during the forming process: 1) The extrusion process must be continuous and uninterrupted within a cycle, especially when the material undergoes large-volume deformation. The material hardens rapidly during this process; interrupting the deformation will cause the work-hardening effect to manifest quickly. To continue extruding, the material needs to be heated and softened. 2) Pressure changes during extrusion must be relatively stable. Sudden pressure loss will interrupt the material's flow and deformation process, causing it to harden. 3) Extrusion speed. Some materials, such as 5-series and 7-series aluminum alloys and magnesium-aluminum alloys, require extrusion while heated. Extrusion at too slow a speed will cause the material to harden due to cooling, making it difficult to form.

[0004] Experiments have shown that a 178mm diameter 5-series aluminum rod, under heating, can be freely extruded to a capacity of 5000 tons or higher. However, for such small parts, it's impractical to use the typical 2-3 square meter worktable of a 5000-ton press, as this would be inconvenient for loading, unloading, and the extrusion process. The solution is to increase the hydraulic cylinder's working pressure. Doubling the cylinder pressure allows for a 30% reduction in cylinder diameter. Currently, commonly used high-pressure hydraulic cylinders can reach 80MPa; compared to the traditional 20MPa cylinder, the cylinder diameter can be reduced to 50% of the traditional cylinder diameter. The reduction in equipment size is considerable.

[0005] Meanwhile, the pressure source for high-pressure cylinders cannot be met by ordinary oil pumps; it must be obtained through a booster device. Taking a system pressure of 20MPa as an example, boosting to 80MPa requires a booster device (booster cylinder) with a booster ratio of 1:4. Similarly, after passing through the booster device, the oil flow rate will decrease to 1 / 4 of its original value, meaning the cylinder's extrusion speed will decrease to 1 / 4 of its pre-boosting speed. Furthermore, since the high-pressure volume of the booster cylinder is fixed, the oil flow rate required for extrusion deformation is often several times the high-pressure volume of the booster cylinder. For machines around 5000 tons, where the cylinders are relatively small, the booster stroke can be increased by adding more boosters and increasing the high-pressure cylinder diameter. However, increasing the extrusion stroke significantly increases the manufacturing cost of the equipment. For equipment exceeding 10,000 tons, which often requires an extrusion stroke of 30-40 mm or even 100 mm, simply increasing the number of booster cylinders to increase the extrusion stroke is impractical.

[0006] This raises the following requirements: 1. Pressure needs to reach 3 to 4 times that of traditional pressure, such as 80 MPa; 2. Sufficient high-pressure flow output to ensure that the hydraulic cylinder completes a sufficient extrusion stroke within one operating cycle; 3. Stable pressure output; 4. Minimal number of booster cylinders to reduce system costs.

[0007] It is clear that existing technology still needs improvement. Summary of the Invention

[0008] The present invention aims to improve at least one technical problem in the prior art.

[0009] This invention provides a staged continuous boosting system, including a working cylinder and a control device, and further comprising: A booster cylinder assembly, comprising at least two booster cylinders connected in parallel and a reversing mechanism, wherein each booster cylinder alternately boosts the pressure of the working cylinder through the reversing mechanism; The number of booster cylinder groups is two or more, and each group of booster cylinder groups has a different boost ratio; Pressure source, wherein there are two or more pressure sources, and one pressure source is shared by one pressure cylinder of each group of pressure cylinders; A monitoring mechanism is used to acquire the real-time working status of each booster cylinder and working cylinder; The control device and the reversing mechanism are both signal connected. The control device selects a group of booster cylinders with different booster ratios to boost the working cylinders at different stages of output pressure according to the real-time working status of each booster cylinder and working cylinder obtained by the detection mechanism. At the same time, it also controls the reversing mechanism of the booster cylinder group in the same group to alternately boost the working cylinders.

[0010] The beneficial effects of this invention are as follows: The graded continuous pressurization system of this invention has two sets of pressurizing cylinders with different pressurization ratios during operation. This allows, firstly, the system to output different pressure values ​​as needed under constant system pressure, adapting to different environments or processing stages. Secondly, the graded continuous pressurization system is equipped with multiple negative pressure sources, and each set of pressurizing cylinders is connected to different negative pressure sources. During the alternating and gradual pressurization process of the pressurizing cylinders in a single set, each negative pressure source supplies pressure to one pressurizing cylinder, ensuring sufficient oil supply speed and improving the pressurization speed. Thirdly, since only one set of pressurizing cylinders is typically pressurizing the working cylinder during the pressurization process, the connection between a negative pressure source and the pressurizing cylinders of different sets allows for full utilization of the negative pressure source, simplifying the overall structure of this graded continuous pressurization system.

[0011] As some sub-solutions of the above technical solution, the booster cylinder assembly includes two booster cylinders, namely a first booster cylinder and a second booster cylinder, and the reversing mechanism includes a first reversing valve and a second reversing valve. The first booster cylinder includes a first input end, a first booster end, and a first output end. Both the first input end and the first booster end are connected to a negative pressure source via the first reversing valve. The second booster cylinder includes a second input end, a second booster end, and a second output end. Both the second input end and the second booster end are connected to a negative pressure source through the second reversing valve. Both the first output terminal and the second output terminal are connected to the oil inlet terminal of the working oil cylinder; The monitoring mechanism includes a first displacement sensor, which is used to acquire the real-time stroke of the first booster cylinder. When the control device detects that the real-time stroke of the first booster cylinder has reached the first pre-limit position, the control device controls the second reversing valve to operate so that another negative pressure source simultaneously supplies oil to the booster end of the second booster cylinder.

[0012] As a sub-solution of the above technical solution, the monitoring mechanism includes a second displacement sensor, which is used to identify the stroke of the working cylinder.

[0013] As a sub-solution of the above technical solution, a first one-way valve is provided between the first output end and the working cylinder, and the first one-way valve causes the oil to flow unidirectionally from the first output end to the working cylinder.

[0014] As a sub-solution of the above technical solution, a second one-way valve is provided between the second output end and the working cylinder, and the second one-way valve allows the oil to flow unidirectionally from the second output end to the working cylinder.

[0015] As a sub-solution of the above technical solution, a third one-way valve is provided between the first output end and the reversing mechanism, and the third one-way valve allows the oil to flow unidirectionally from the reversing mechanism to the first output end.

[0016] As a sub-solution of the above technical solution, a fourth check valve is provided between the second output end and the reversing mechanism, and the fourth check valve allows the oil to flow unidirectionally from the reversing mechanism to the second output end. Attached Figure Description

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the staged continuous boosting system of the present invention.

[0018] In the attached diagram: 1 - Working hydraulic cylinder; 31-Booster cylinder assembly; 311-First booster cylinder; 311a-First input terminal; 311b-First booster terminal; 311c-First output terminal; 312-First booster cylinder; 312a-First input terminal; 312b-First booster terminal; 312c-First output terminal; 321 - First directional control valve; 322 - Second directional control valve; 4-Pressure source; 51-First displacement sensor; 52-Second displacement sensor; 7-First check valve; 8-Second check valve; 9-Third check valve. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] The following is combined with Figure 1 Embodiments of the present invention will be described.

[0021] This embodiment provides a staged continuous boosting system according to the present invention, such as... Figure 1 As shown, the system includes a working cylinder 1 and a control device, as well as a booster cylinder group 31, a pressure source 4, and a monitoring mechanism.

[0022] The booster cylinder group 31 includes at least two booster cylinders connected in parallel and a reversing mechanism. Each booster cylinder alternately boosts the working cylinder 1 through the reversing mechanism. There are two or more booster cylinder groups 31, and each group of booster cylinder groups 31 has a different boosting ratio. For example, the boosting ratio of one group of booster cylinder groups 31 is 2:1, and the boosting ratio of another group of booster cylinder groups 31 is 4:1, so as to adapt to different pressure output requirements.

[0023] There are two or more pressure sources 4. Each pressure cylinder in each pressure cylinder group 31 shares one pressure source 4. That is, one pressure cylinder in the same group is connected to one pressure source 4, and the other pressure cylinder is connected to another pressure source 4, so as to ensure the independence and stability of oil supply.

[0024] The monitoring mechanism is used to obtain the real-time working status of each booster cylinder and working cylinder 1. The real-time working status may include parameters such as pressure value and stroke position.

[0025] The control device and the reversing mechanism are both signal-connected. Based on the real-time operating status obtained from the monitoring mechanism, the control device can select different booster cylinder groups 31 with varying boost ratios to boost the working cylinder 1 at different pressure output stages. Simultaneously, it controls the reversing mechanism of the booster cylinder groups 31 within the same group to alternately boost the working cylinder 1. This configuration allows for the selection of booster cylinder groups 31 with lower boost ratios during low-pressure output and high-pressure output during high-pressure output. Furthermore, the alternating operation of booster cylinders within the same group avoids efficiency bottlenecks associated with single-group or single-cylinder operation, contributing to improved continuity of the overall boosting process.

[0026] Furthermore, in one embodiment of the present invention, the booster cylinder group 31 includes two booster cylinders, namely a first booster cylinder 311 and a second booster cylinder, and the reversing mechanism includes a first reversing valve 321 and a second reversing valve 322. The first booster cylinder 311 includes a first input end 311a, a first booster end 311b, and a first output end 311c. Both the first input end 311a and the first booster end 311b are connected to a negative pressure source through a first reversing valve 321. The operation of the first reversing valve 321 can control the negative pressure source to supply oil to either the first input end 311a or the first booster end 311b. The second booster cylinder includes a second input end a, a second booster end 312b, and a second output end 312c. Both the second input end a and the second booster end 312b are connected to a negative pressure source through a second reversing valve 322. Similarly, the operation of the second reversing valve 322 can control the negative pressure source to supply oil to either the second input end 312a or the second booster end 312b. Both the first output terminal 311c and the second output terminal 312c are connected to the oil inlet of the working cylinder 1 to deliver the pressurized oil to the working cylinder 1. The monitoring mechanism includes a first displacement sensor 51, which is used to acquire the real-time stroke of the first pressurizing cylinder 311. For example, a grating ruler or magnetic grating ruler can be set on the cylinder body of the first pressurizing cylinder 311, and stroke detection can be achieved in conjunction with a corresponding reading head. When the control device acquires that the real-time stroke of the first pressurizing cylinder 311 reaches the first pre-limit position (this pre-limit position can be preset according to the maximum effective stroke of the first pressurizing cylinder 311, for example, 90% of its maximum stroke), the control device controls the second reversing valve 322 to operate, so that another negative pressure source simultaneously supplies oil to the pressurizing end 312b of the second pressurizing cylinder. At this time, the second pressurizing cylinder begins to output pressurized oil to the working cylinder 1, realizing alternating pressurization with the first pressurizing cylinder 311.

[0027] To enable more precise pressure control of the working cylinder 1 by the control device, the present invention also includes a second displacement sensor 52. That is, the monitoring mechanism includes the second displacement sensor 52, which is used to identify the stroke of the working cylinder 1. Its installation method can refer to that of the first displacement sensor 51, for example, by mounting it on the piston rod of the working cylinder 1. The control device can combine the real-time stroke of the working cylinder 1 to determine its current required pressure value, thereby more rationally selecting the booster cylinder group 31 and controlling the alternation timing of the booster cylinders.

[0028] Furthermore, a first check valve 7 is provided between the first output end 311c and the working cylinder 1. The first check valve 7 allows the oil to flow unidirectionally from the first output end 311c to the working cylinder 1, so as to prevent the oil in the working cylinder 1 from flowing back to the first booster cylinder 311 and ensure the stable establishment of pressure in the working cylinder 1.

[0029] Similarly, a second one-way valve 8 is provided between the second output end 312c and the working cylinder 1. The second one-way valve 8 allows the oil to flow unidirectionally from the second output end 312c to the working cylinder 1, so as to prevent the oil in the working cylinder 1 from flowing back to the second booster cylinder, and further ensure the stable establishment of pressure in the working cylinder 1.

[0030] To make the oil supply process of the first booster cylinder 311 more stable, the present invention also provides a third one-way valve 9, that is, a third one-way valve 9 is provided between the first output end 311c and the reversing mechanism. The third one-way valve 9 allows the oil to flow unidirectionally from the reversing mechanism to the first output end 311c, so as to avoid the reverse flow of oil affecting the output of the first booster cylinder 311 when the reversing mechanism is activated.

[0031] Accordingly, a fourth check valve is provided between the second output end 312c and the reversing mechanism. The fourth check valve allows the oil to flow unidirectionally from the reversing mechanism to the second output end 312c, so as to avoid the reverse flow of oil affecting the output of the second booster cylinder when the reversing mechanism is activated, and to ensure the stability of the oil supply to the second booster cylinder.

[0032] The working principle of the staged continuous boosting system of the present invention is as follows: Taking a system pressure of 20MPa as an example, the system contains two-stage booster cylinder groups 31, each of which includes two booster cylinders: Since each booster cylinder group 31 only includes two booster cylinders, the minimum number of negative pressure sources can be configured as two. The boosting ratio of the first-stage booster cylinder group 31 is 1:2, and the boosting ratio of the second-stage booster cylinder group 31 is 1:4.

[0033] The control device achieves three different working states based on the feedback from the second position sensor of the monitoring mechanism to the working cylinder 1, so as to adapt to the pressure and speed requirements of different process stages.

[0034] State 1: Pressure source 4 directly supplies oil In this state, the control device keeps each reversing mechanism in the neutral position, and pressure sources 4 (YP1) and 4 (YP2) directly supply oil to the working cylinder 1. It is possible to select a single pressure source 4 supplying oil independently or two or more pressure sources 4 supplying oil simultaneously, with the system speed being fastest when both pressure sources 4 supply oil simultaneously. In this state, the output pressure of the working cylinder 1 can reach the system's maximum base pressure P (in this embodiment, P is 20 MPa), suitable for the rapid feed requirements in the initial stage of the process.

[0035] State 2: First-stage pressure boosting cylinder assembly 31 operates and outputs pressure. When the monitoring device detects that the pressure of the working cylinder 1 is close to or reaches 20MPa and the stroke of the working cylinder 1 is in the middle and front section, the control device switches to the first-stage boosting mode. By controlling the operation of the first and second reversing valves 322, the first boosting cylinder and the second boosting cylinder of the first-stage boosting cylinder group 31 take turns to output pressure oil to the working cylinder 1.

[0036] The monitoring mechanism's pressure sensor detects the output pressure of the booster cylinders in real time, and the displacement sensor acquires the stroke position of each booster cylinder in real time. When the real-time stroke of the first booster cylinder 311 reaches the first pre-limit position (preset to 90% of its maximum effective stroke), the control device controls the corresponding reversing valve of the second booster cylinder to operate in advance, so that another pressure source 4 supplies oil to the boosting end of the second booster cylinder. The second booster cylinder begins to output pressurized oil, achieving seamless alternating boosting with the first booster cylinder 311 and the first booster cylinder 312. When the output pressure of the second booster cylinder stabilizes, the first booster cylinder 311, which has reached its forward limit, retracts under the control of the reversing valve, resetting to its initial position to prepare for the second output.

[0037] In this state, the maximum output pressure of the system reaches 1 / 2 of the highest working pressure P1 (in this embodiment, P1 is 80MPa, so the maximum output pressure in this state is 40MPa), and the output speed drops to 1 / 2 of the direct oil supply speed of pressure source 4. This is suitable for medium-pressure long-stroke stages that account for more than 50% in forging or extrusion processes.

[0038] State 3: Second-stage pressure boosting cylinder assembly 31 operates and outputs pressure. When the monitoring device detects that the working cylinder 1 has entered the last 1 / 3 of its stroke and the pressure demand has increased to above 40MPa, the control device switches to the second-stage boosting mode. Using the boosting cylinders of the second-stage boosting cylinder group 31 as the third and fourth boosting cylinders, the third and fourth directional valves are controlled to operate, causing the first and second boosting cylinders of the second-stage boosting cylinder group 31 to alternately operate and output pressure.

[0039] Its alternating working logic is consistent with that of the first-stage booster cylinder group 31: when the displacement sensor detects that the stroke of the first booster cylinder (or the second booster cylinder) of the second-stage booster cylinder group 31 is close to the pre-limit position, the control device triggers the second booster cylinder (or the first booster cylinder) to operate in advance, and the pressure source 4YP1 (or YP2) supplies oil to the corresponding booster cylinder to achieve continuous boosting; after the pressure of the newly operating booster cylinder stabilizes, the booster cylinder that has reached its limit retracts and resets. In this state, the maximum output pressure of the system is the highest working pressure P1 (80MPa in this embodiment), and the output speed is reduced to 1 / 4 of the direct oil supply speed of the pressure source 4, which is suitable for the high-pressure extrusion stage in the later stage of the process.

[0040] In the initial low-pressure, long-stroke stage, the system's speed drops to a maximum of half the speed of direct oil supply from pressure source 4 (as in the example above). Compared to traditional constant-ratio booster systems (such as the 1:4 ratio here), the time is reduced by nearly half, efficiency is improved, and material cooling is significantly reduced. This allows for sufficient time for the final high-pressure extrusion stage.

[0041] Secondly, this system can increase the output volume of each stage of the booster cylinder group 31 by simply connecting the horizontal booster cylinders in parallel, thereby increasing the forward displacement of the working cylinder 1 in a single operation; or it can add booster cylinder groups 31 with different booster ratios to form a 3-stage or 4-stage pressure boosting system. The addition of the corresponding valve groups is relatively simple and has good scalability.

[0042] The preferred embodiments of the present invention have been described in detail above, but the present disclosure is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of the present disclosure.

[0043] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

Claims

1. A staged continuous pressurization system, comprising a working cylinder (1) and a control device, characterized in that: Also includes: The booster cylinder group (31) includes at least two booster cylinders connected in parallel and a reversing mechanism. Each of the booster cylinders alternately boosts the working cylinder (1) through the reversing mechanism. The number of the booster cylinder group (31) is two or more, and each group of the booster cylinder group (31) has a different boost ratio; Pressure source (4), there are two or more pressure sources (4), and one pressure source (4) is shared by one pressure cylinder of each group of pressure cylinder group (31). The monitoring mechanism is used to obtain the real-time working status of each booster cylinder and working cylinder (1); The control device and the reversing mechanism are both signal connected. The control device selects a different pressure boosting cylinder group (31) for the working cylinder (1) to boost pressure according to the real-time working status of each boosting cylinder and the working cylinder (1) obtained by the detection mechanism at different stages of output pressure. At the same time, it also controls the reversing mechanism of the boosting cylinder group (31) in the same group to alternately boost the working cylinder (1).

2. The staged continuous boosting system according to claim 1, characterized in that: The booster cylinder group (31) includes two booster cylinders, namely a first booster cylinder (311) and a second booster cylinder, and the reversing mechanism includes a first reversing valve (321) and a second reversing valve (322). The first booster cylinder (311) includes a first input end (311a), a first booster end (311b), and a first output end (311c). The first input end (311a) and the first booster end (311b) are both connected to the negative pressure source through the first reversing valve (321). The second booster cylinder includes a second input end, a second booster end, and a second output end. Both the second input end and the second booster end are connected to a negative pressure source through the second reversing valve (322). Both the first output terminal (311c) and the second output terminal are connected to the oil inlet of the working cylinder (1); The monitoring mechanism includes a first displacement sensor (51), which is used to acquire the real-time stroke of the first booster cylinder (311); When the control device obtains that the real-time stroke of the first booster cylinder (311) has reached the first pre-limit position, the control device controls the second reversing valve (322) to operate so that another negative pressure source simultaneously supplies oil to the booster end of the second booster cylinder.

3. The staged continuous boosting system according to claim 2, characterized in that: The monitoring mechanism includes a second displacement sensor (52) for identifying the stroke of the working cylinder (1).

4. The staged continuous boosting system according to claim 3, characterized in that: A first check valve (7) is provided between the first output end (311c) and the working cylinder (1). The first check valve (7) allows the oil to flow unidirectionally from the first output end (311c) to the working cylinder (1).

5. The staged continuous boosting system according to claim 4, characterized in that: A second check valve (8) is provided between the second output end and the working cylinder (1). The second check valve (8) allows the oil to flow unidirectionally from the second output end to the working cylinder (1).

6. The staged continuous boosting system according to claim 5, characterized in that: A third check valve (9) is provided between the first output end (311c) and the reversing mechanism. The third check valve (9) allows the oil to flow unidirectionally from the reversing mechanism to the first output end (311c).

7. The staged continuous boosting system according to claim 6, characterized in that: A fourth check valve is provided between the second output end and the reversing mechanism, which allows the oil to flow unidirectionally from the reversing mechanism to the second output end.

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