A hydraulic system for a powder forming press

Abstract

This utility model discloses a hydraulic system for a powder molding press, including: an oil tank, a component mounting cabinet, and an oil cooler. The upper surface of the oil tank, located inside the component mounting cabinet, houses an oil filler port, a high-low pressure dual pump, a return oil filter, a first oil circuit block, a second oil circuit block, and a liquid level and temperature sensor. A liquid level gauge and a junction box are installed on the side of the oil tank, with an electrical control unit inside the junction box. The oil cooler is fixedly installed above the component mounting cabinet, which also houses a high-pressure filter and two accumulators. The high-low pressure dual pump is connected to the first oil circuit block and the oil tank via two pipelines, and the high-low pressure dual pump is equipped with a remote communication control structure. This utility model uses a high-low pressure dual pump in conjunction with dual oil inlet channels (HP / NP) and a plug-in check valve assembly within the first oil circuit block. It can automatically switch between high-pressure / low-pressure or dual-pump combined oil supply modes according to process requirements, satisfying both high-speed, low-pressure filling needs and achieving high-pressure precision molding, resulting in energy saving and high efficiency.

Description

Technical Field

[0001] This utility model relates to the field of powder material forming technology, specifically a hydraulic system for a powder forming press. Background Technology

[0002] A powder forming press is a specialized piece of equipment that presses metal or non-metal powders into pre-shaped blanks under high pressure. The performance of its hydraulic system directly determines the density uniformity, dimensional accuracy, and production efficiency of the formed products. Currently, most common powder forming press hydraulic systems use traditional single-pump or fixed-displacement pump oil supply methods, which have the following prominent problems: 1. Insufficient pressure control precision: In complex multi-action pressing cycles, it is difficult to achieve rapid, precise switching and stable maintenance of pressure at different stages, which can easily lead to defects such as product delamination and cracks. 2. Low energy utilization: During pressure holding and pressure relief operations, a large amount of hydraulic energy is dissipated as heat, which not only wastes energy but also causes the oil temperature to rise, affecting the stability of the system. 3. Slow system response: Traditional oil circuit design is complex and valve group response is lagging, making it difficult to meet the requirements of high-speed and high-frequency pressing processes.

[0003] Therefore, we propose a hydraulic system for a powder forming press to address the problems mentioned above. Utility Model Content

[0004] The purpose of this invention is to provide a hydraulic system for a powder forming press to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a hydraulic system for a powder forming press, comprising: an oil tank, a component mounting cabinet, and an oil cooler. The upper surface of the oil tank, located inside the component mounting cabinet, is equipped with an oil filler port, a high- and low-pressure dual pump, a return oil filter, a first oil circuit block, a second oil circuit block, and a liquid level and temperature sensor. A liquid level gauge and a junction box are installed on the side of the oil tank. An electrical control unit is installed inside the junction box. The oil cooler is fixedly installed above the component mounting cabinet. A high-pressure filter and two accumulators are also installed inside the component mounting cabinet. The high-low pressure dual pump is connected to the first oil circuit block and the oil tank through two pipelines. The first oil suction filter is installed at the end of the pipeline located inside the oil tank, and the high-low pressure dual pump is equipped with a remote communication control structure. The first oil circuit block is directly connected to the oil tank through a pipeline. This pipeline is a return oil pipeline, and a return oil filter is installed on it. The first oil circuit block has two built-in oil inlet channels (HP and NP), one oil outlet channel and one oil return channel. The two oil inlet channels are connected to one oil outlet channel at the same time. The NP oil inlet channel is connected to a plug-in check valve, and another plug-in check valve is installed on the oil outlet channel. The first oil circuit block is equipped with a plug-in unloading valve, a plug-in overflow valve and two first plug-in solenoid ball valves. One of the first plug-in solenoid ball valves is connected to a pressure sensor and a pressure measuring connector. A first plug-in solenoid ball valve is connected between the oil outlet channel and the oil return channel, and another first plug-in solenoid ball valve is connected between the NP oil inlet channel and the oil return channel. The connection between the oil inlet channel and the oil outlet channel is connected to the return oil channel, and a plug-in relief valve is provided at the connection. The NP oil inlet channel is also connected to the return oil channel through a plug-in unloading valve. The plug-in unloading valve is also connected to the oil inlet of the plug-in relief valve. The plug-in unloading valve is connected to a pressure test connector. The oil outlet channel of the first oil circuit block is connected to the high-pressure filter through a pipeline, the high-pressure filter is connected to the second oil circuit block through a pipeline, and the oil return port of the second oil circuit block is directly connected to the oil return channel of the first oil circuit block through a pipeline. The second oil circuit block is equipped with a high-performance proportional pressure reducing valve, a third oil circuit block, a fourth oil circuit block, a fifth oil circuit block, and a reserved valve group for the material return cylinder.

[0006] Preferably, the oil tank is connected to the oil cooler through two pipes, wherein the oil outlet pipe is equipped with a second oil suction filter at the end of the oil tank, and an oil pump is also installed on the oil outlet pipe, which is located inside the cabinet where the oil cooler is located.

[0007] Preferably, the high-performance proportional pressure reducing valve is connected to the oil outlet passage of the second oil circuit block, the high-performance proportional pressure reducing valve is connected to the third oil circuit block, and the oil return passage of the third oil circuit block is connected to the oil return passage in the second oil circuit block.

[0008] Preferably, the third oil circuit block is stacked with a balance valve, another plug-in check valve, another first plug-in solenoid ball valve, a first hydraulic check valve, and a third solenoid directional valve. The balance valve is connected to the fourth oil circuit block through a pipeline. The fourth oil circuit block is equipped with two first plug-in solenoid ball valves, one plug-in throttle valve, and an accumulator. The fourth oil circuit block outputs to the foaming machine spray gun through a pipeline. A pressure sensor is installed on this pipeline. The oil return port of the foaming machine spray gun is connected to the oil return port of the balance valve through a pipeline. Pressure test connectors are installed on both the oil outlet and return pipelines between the balance valve and the fourth oil circuit block.

[0009] Preferably, a second solenoid directional valve is also installed on the second oil circuit block. The second solenoid directional valve is connected to a second hydraulically controlled check valve. The second hydraulically controlled check valve is connected to the return oil circuit of the fifth oil circuit block. The second solenoid directional valve is connected to the inlet oil circuit of the fifth oil circuit block. The inlet oil circuit of the second solenoid directional valve is connected to the inlet oil circuit of the second oil circuit block. The return oil circuit of the second solenoid directional valve is connected to the return oil circuit of the second oil circuit block. A pressure test connector is installed on the oil circuit between the second solenoid directional valve and the fifth oil circuit block.

[0010] Preferably, the fifth oil circuit block is connected to another accumulator, a pressure sensor is installed in the oil inlet of the fifth oil circuit block, a pressure sensor is installed between the accumulator and the oil return of the fifth oil circuit block, a throttle valve, an overflow valve and a second plug-in solenoid ball valve are also installed in the oil return of the fifth oil circuit block, and the oil inlet and oil return of the fifth oil circuit block are connected to another set of foaming machine spray guns.

[0011] Preferably, the second oil circuit block is also equipped with a buffer valve group and a reserved valve group for the discharge cylinder. The buffer valve group includes a stacked pressure reducing valve. A pressure gauge and a first solenoid directional valve are installed on the stacked pressure reducing valve. The oil inlet and oil return lines in the stacked pressure reducing valve are connected. The stacked pressure reducing valve controls the oil inlet and oil return through the valve core. The oil inlet and oil return ports of the first solenoid directional valve are respectively connected to pressure testing connectors.

[0012] Compared with the prior art, the beneficial effects of this utility model are: 1. The high and low pressure dual pumps are combined with the dual oil inlet channels (HP / NP) and plug-in check valve group in the first oil circuit block. The high pressure / low pressure or dual pump combined oil supply mode can be automatically switched according to process requirements. It can meet the high speed and low pressure filling requirements and achieve high pressure precision molding, which is energy-saving and efficient. 2. The system is equipped with high-performance proportional pressure reducing valves, plug-in relief valves, unloading valves, balancing valves and multiple pressure sensors at key nodes to achieve independent, precise and continuous adjustment of the pressure of different actuators (such as main pressure cylinders and foaming machine spray guns), which significantly improves the quality of molded products. 3. An integrated accumulator bank stores energy during low-pressure or intermittent periods and releases it during peak demand, effectively mitigating pressure fluctuations, reducing installed power, and resulting in significant energy savings. The oil cooler is linked to a liquid level and temperature sensor to achieve intelligent cooling of the hydraulic oil, ensuring stable system operation under prolonged high-temperature conditions. 4. The core valve group is integrated by using multiple standardized oil circuit blocks (first to fifth oil circuit blocks), which has a compact structure, clear layout, greatly reduces external pipeline connections, improves system reliability, facilitates installation, commissioning and maintenance, and reserves an interface for the unloading cylinder valve group, which has strong expandability; 5. All key oil circuits in the system are equipped with pressure sensors, pressure testing connectors, and safety valve assemblies to monitor system pressure in real time and provide functions such as automatic overload relief and abnormal alarms. The high- and low-pressure dual pumps support remote communication, laying the foundation for intelligent equipment monitoring and remote fault diagnosis. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the internal structure of the protective cover in this utility model; Figure 3 This is a schematic diagram of the structure above the oil tank in this utility model; Figure 4 This is a schematic diagram of the pipeline of this utility model; Figure 5 This is a schematic diagram of the pipeline of the first oil passage block in this utility model; Figure 6 This utility model Figure 4 Enlarged view of point A; Figure 7 This is a schematic diagram of the pipeline of the fifth oil circuit block in this utility model; Figure 8 This utility model Figure 4 Enlarged view of point B; Figure 9 This utility model Figure 4 Enlarged view of point C.

[0014] In the diagram: 1. Oil tank; 2. Level gauge; 3. Filler port; 4. First suction filter; 5. Second suction filter; 8. High and low pressure dual pump; 9. Return oil filter; 10. Junction box; 11. High pressure filter; 12. Oil cooler; 13. First oil manifold block; 15. Pressure sensor; 16. Pressure test connector; 17. Plug-in check valve; 18. Plug-in relief valve; 19. Plug-in unloading valve; 20. First plug-in solenoid ball valve; 21. Second oil manifold block; 22. High-performance proportional pressure reducing valve; 24. Third solenoid ball valve. 25. Directional control valve; 26. First hydraulically controlled check valve; 27. Third manifold block; 28. Balance valve; 29. ​​Fourth manifold block; 30. Insert-type throttle valve; 31. First solenoid directional control valve; 32. Second solenoid directional control valve; 33. Second hydraulically controlled check valve; 34. Fifth manifold block; 35. Second insert-type solenoid ball valve; 36. Relief valve; 37. Throttling valve; 38. Reserved valve assembly for unloading cylinder; 39. Liquid level and temperature sensor; 40. Pressure gauge; 41. Accumulator; 52. Stacked pressure reducing valve; 63. Component mounting cabinet. Detailed Implementation

[0015] 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.

[0016] Please see Figure 1-9 This utility model provides a technical solution: a hydraulic system for a powder molding press, including: an oil tank 1, a component mounting cabinet 51 and an oil cooler 12. The upper surface of the oil tank 1 is located inside the component mounting cabinet 51 and is equipped with an oil filling port 3, a high and low pressure dual pump 8, a return oil filter 9, a first oil circuit block 13, a second oil circuit block 21 and a liquid level and temperature sensor 38. A liquid level gauge 2 and a junction box 10 are installed on the side of the oil tank 1. The liquid level gauge 2 is used to read the liquid level in the oil tank 1. An electrical control unit is set inside the junction box 10. The oil cooler 12 is fixedly installed on the top of the component mounting cabinet 51. A high pressure filter 11 and two accumulators 40 are also installed inside the component mounting cabinet 51. The oil tank 1 is connected to the oil cooler 12 through two pipes. The oil outlet pipe is located at the end of the oil tank 1 and a second oil suction filter 5 is installed. An oil pump is also installed on the oil outlet pipe. The oil pump is located in the cabinet where the oil cooler 12 is located. The oil pump and the oil cooler 12 work together, and in conjunction with the liquid level and temperature sensor 38, to cool and control the temperature of the hydraulic oil in the oil tank 1.

[0017] The high-low pressure dual pump 8 is connected to the first oil circuit block 13 and the oil tank 1 through two pipelines. The first oil suction filter 4 is installed at the end of the pipeline inside the oil tank 1. The high-low pressure dual pump 8 is equipped with a remote communication control structure to realize remote control of pumping oil.

[0018] The first oil circuit block 13 is directly connected to the oil tank 1 via a pipeline. This pipeline is a return oil pipeline, and a return oil filter 9 is installed on it to filter the return oil.

[0019] The first oil circuit block 13 has two built-in oil inlet channels (HP and NP), one oil outlet channel and one oil return channel. The two oil inlet channels are simultaneously connected to one oil outlet channel. The NP oil inlet channel is connected to a plug-in check valve 17, and another plug-in check valve 17 is installed on the oil outlet channel. This allows the two oil inlet channels to supply oil to one oil outlet channel at the same time, or a single HP oil inlet channel to supply oil to the oil outlet channel. The first oil circuit block 13 is equipped with a plug-in unloading valve 19, a plug-in overflow valve 18 and two first plug-in solenoid ball valves 20. One of the first plug-in solenoid ball valves 20 is connected to a pressure sensor 15 and a pressure test connector 16. One first plug-in solenoid ball valve 20 is connected between the oil outlet channel and the oil return channel, and another first plug-in solenoid ball valve 20 is connected between the NP oil inlet channel and the oil return channel. The connection between the two oil inlet channels and the oil outlet channels is connected to the return oil channel, and a plug-in relief valve 18 is installed at the connection. The NP oil inlet channel is also connected to the return oil channel through a plug-in unloading valve 19. The plug-in unloading valve 19 is also connected to the oil inlet of the plug-in relief valve 18. The plug-in unloading valve 19 is connected to a pressure test connector 16. When the pressure of the NP oil inlet channel is overloaded, the plug-in unloading valve 19 opens the passage to the return oil channel to relieve pressure through the return oil channel. Under normal circumstances, the plug-in unloading valve 19 is directly connected to the plug-in relief valve 18, and the plug-in relief valve 18 relieves pressure for normal pressure relief. Another pressure sensor 15 and pressure testing connector 16 are also installed on the oil outlet channel. When the pressure in the oil outlet channel is overloaded, the pressure testing connector 16 identifies the overload and opens the passage between the oil outlet channel and the return channel through the first plug-in solenoid ball valve 20 to release the hydraulic oil in the oil outlet channel. The pressure sensor 15 then reads the oil pressure in the oil outlet channel.

[0020] The oil outlet channel of the first oil circuit block 13 is connected to the high-pressure filter 11 through a pipeline. The high-pressure filter 11 is connected to the second oil circuit block 21 through a pipeline. The oil return port of the second oil circuit block 21 is directly connected to the oil return channel of the first oil circuit block 13 through a pipeline.

[0021] The second oil circuit block 21 is equipped with a high-performance proportional pressure reducing valve 22, a third oil circuit block 26, a fourth oil circuit block 28, a fifth oil circuit block 33, and a pre-reserved valve group 37 for the unloading cylinder. The high-performance proportional pressure reducing valve 22 is connected to the oil outlet passage of the second oil circuit block 21. The high-performance proportional pressure reducing valve 22 is connected to the third oil circuit block 26. The return oil passage of the third oil circuit block 26 is connected to the return oil passage in the second oil circuit block 21. The hydraulic oil is pressure controlled by the high-performance proportional pressure reducing valve 22 before entering the third oil circuit block 26, and then flows back to the return oil passage of the second oil circuit block 21 from the third oil circuit block 26. The third oil circuit block 26 is stacked with a balance valve 27, another plug-in check valve 17, another first plug-in solenoid ball valve 20, a first hydraulic check valve 25 and a third solenoid directional valve 24. The balance valve 27 is connected to the fourth oil circuit block 28 through a pipeline. The fourth oil circuit block 28 is equipped with two first plug-in solenoid ball valves 20, a plug-in throttle valve 29 and an accumulator 40. The fourth oil circuit block 28 outputs to the foaming machine spray gun through a pipeline. A pressure sensor 15 is installed on this pipeline. The oil return port of the foaming machine spray gun is connected to the oil return port of the balance valve 27 through a pipeline. After the hydraulic oil enters the third oil circuit block 26, it passes through the third solenoid directional valve 24, the first hydraulic control check valve 25, the first plug-in solenoid ball valve 20, the plug-in check valve 17 and the balance valve 27 in sequence to supply the fourth oil circuit block 28, and then to the foaming machine spray gun. At the same time, the accumulator 40 replenishes or releases the pressure of the foaming machine spray gun to achieve precise control of the speed of the foaming machine spray gun. The hydraulic oil of the foaming machine spray gun then returns through the pipeline to the balance valve 27, the plug-in check valve 17, the first plug-in solenoid ball valve 20, the first hydraulic control check valve 25 and the third solenoid directional valve 24 in sequence, and then returns to the return oil channel of the second oil circuit block 21. Pressure test connectors 16 are installed on both the oil outlet and return lines between the balance valve 27 and the fourth oil circuit block 28.

[0022] A second solenoid directional valve 31 is also installed on the second oil circuit block 21. The second solenoid directional valve 31 is connected to the second hydraulic control check valve 32. The second hydraulic control check valve 32 is connected to the return oil circuit of the fifth oil circuit block 33. The second solenoid directional valve 31 is connected to the inlet oil circuit of the fifth oil circuit block 33. The inlet oil circuit of the second solenoid directional valve 31 is connected to the inlet oil circuit of the second oil circuit block 21. The return oil circuit of the second solenoid directional valve 31 is connected to the return oil circuit of the second oil circuit block 21. A pressure test connector 16 is installed on the oil circuit between the second solenoid directional valve 31 and the fifth oil circuit block 33. Hydraulic oil enters the second solenoid directional valve 31 through the inlet of the second oil circuit block 21, and is then output to the fifth oil circuit block 33. The return oil from the fifth oil circuit block 33 flows back to the second solenoid directional valve 31 through the second hydraulic control check valve 32, and returns to the return oil circuit of the second oil circuit block 21 from the return oil circuit.

[0023] The fifth oil circuit block 33 is connected to another accumulator 40. A pressure sensor 15 is installed in the oil inlet of the fifth oil circuit block 33. A pressure sensor 15 is installed between the accumulator 40 and the oil return of the fifth oil circuit block 33. A throttle valve 36, an overflow valve 35 and a second plug-in solenoid ball valve 34 are also installed in the oil return of the fifth oil circuit block 33. The oil inlet and oil return of the fifth oil circuit block 33 are connected to another set of foaming machine spray guns. The second oil circuit block 21 is also equipped with a buffer valve group and a pre-reserved valve group 37 for the unloading cylinder. The buffer valve group includes a stacked pressure reducing valve 41. The stacked pressure reducing valve 41 is equipped with a pressure gauge 39 and a first solenoid directional valve 30. The hydraulic oil of the second oil circuit block 21 enters the first solenoid directional valve 30 through the stacked pressure reducing valve 41 and then flows back to the return oil circuit of the second oil circuit block 21. The inlet and return oil circuits in the stacked pressure reducing valve 41 are connected. The stacked pressure reducing valve 41 controls the inlet and return oil through the valve core. The inlet and return oil ports of the first solenoid directional valve 30 are respectively connected to the pressure test connector 16.

[0024] The two oil ports of the pre-reserved valve group 37 of the unloading cylinder are also equipped with pressure test connectors 16.

[0025] Working principle: After the system starts, the high and low pressure dual pump 8 draws oil from the oil tank 1 through the first suction filter screen 4 and pumps the hydraulic oil into the first oil circuit block 13. The first oil circuit block 13 serves as the core control unit. Through its internal two oil inlet channels (HP and NP), plug-in check valve 17, plug-in relief valve 18, plug-in unloading valve 19, and first plug-in solenoid ball valve 20, the system realizes the pressure control, switching, and safety protection of the oil source. The system can select the high pressure pump to supply oil alone, the low pressure pump to supply oil alone, or the dual pump combined oil supply mode according to the actual working conditions.

[0026] After initial pressure stabilization and directional control, the hydraulic oil is purified by the high-pressure filter 11 and then enters the second oil circuit block 21. Here, the high-performance proportional pressure reducing valve 22 performs precise secondary regulation of the oil pressure. Subsequently, the hydraulic oil is distributed to different execution branches. Main pressing / action branch: Hydraulic oil enters the third oil circuit block 26 through the third solenoid directional valve 24, the first hydraulic control check valve 25, etc., and is controlled by the balance valve 27 to flow to the fourth oil circuit block 28, driving the main pressing cylinder or the foaming machine spray gun and other actuators. The accumulator 40 in this branch plays a role in compensation and flow stabilization, ensuring smooth operation and controllable speed. The return oil returns to the system through the balance valve 27 and the corresponding valve group. Auxiliary action branch: Hydraulic oil controls the fifth oil circuit block 33 through the second solenoid directional valve 31 and the second hydraulic control check valve 32, driving another set of actuators. This branch is also equipped with an accumulator 40, a throttle valve 36 and an overflow valve 35 for precise control. System protection and buffering: The buffer valve group includes a stacked pressure reducing valve 41 to absorb hydraulic shocks, and the unloading cylinder has a reserved valve group 37 to provide an interface for subsequent functional expansion; Throughout the entire operation, the oil cooler 12 circulates and cools the hydraulic oil based on the feedback from the liquid level and temperature sensor 38. The pressure sensors 15 and pressure test connectors 16 throughout the system monitor the pressure at each point in real time. The electrical control unit, located in the junction box 10, comprehensively processes these signals and controls the operation of each solenoid valve, thereby achieving automated, precise, safe, and reliable operation of the entire powder molding process.

[0027] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0028] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A hydraulic system for a powder forming press, comprising: The oil tank (1), component mounting cabinet (51) and oil cooler (12) are characterized in that: the upper surface of the oil tank (1) is equipped with an oil filling port (3), a high and low pressure dual pump (8), a return oil filter (9), a first oil circuit block (13), a second oil circuit block (21) and a liquid level and temperature sensor (38) inside the component mounting cabinet (51); a liquid level gauge (2) and a junction box (10) are installed on the side of the oil tank (1); an electrical control unit is set in the junction box (10); an oil cooler (12) is fixedly installed on the top of the component mounting cabinet (51); a high pressure filter (11) and two accumulators (40) are also installed in the component mounting cabinet (51); The high-low pressure dual pump (8) is connected to the first oil circuit block (13) and the oil tank (1) through two pipelines. The first oil suction filter (4) is installed at the end of the pipeline inside the oil tank (1), and the high-low pressure dual pump (8) is equipped with a remote communication control structure. The first oil circuit block (13) is directly connected to the oil tank (1) through a pipeline. This pipeline is a return oil pipeline, and a return oil filter (9) is installed on it. The first oil circuit block (13) has two inlet channels (HP and NP), one outlet channel and one return channel. The two inlet channels are connected to one outlet channel. The NP inlet channel is connected to a plug-in check valve (17). Another plug-in check valve (17) is installed on the outlet channel. The first oil circuit block (13) is equipped with a plug-in unloading valve (19), a plug-in overflow valve (18) and two first plug-in solenoid ball valves (20). One of the first plug-in solenoid ball valves (20) is connected to a pressure sensor (15) and a pressure measuring connector (16). A first plug-in solenoid ball valve (20) is connected between the outlet channel and the return channel. Another first plug-in solenoid ball valve (20) is connected between the NP inlet channel and the return channel. The oil inlet channel and the oil outlet channel are connected to the return oil channel at the connection point, and a plug-in relief valve (18) is provided at the connection point. The NP oil inlet channel is also connected to the return oil channel through a plug-in unloading valve (19). The plug-in unloading valve (19) is also connected to the oil inlet of the plug-in relief valve (18). The plug-in unloading valve (19) is connected to a pressure test connector (16). The oil outlet channel of the first oil circuit block (13) is connected to the high pressure filter (11) through a pipeline, the high pressure filter (11) is connected to the second oil circuit block (21) through a pipeline, and the oil return hole of the second oil circuit block (21) is directly connected to the oil return channel of the first oil circuit block (13) through a pipeline. The second oil circuit block (21) is equipped with a high-performance proportional pressure reducing valve (22), a third oil circuit block (26), a fourth oil circuit block (28), a fifth oil circuit block (33), and a pre-reserved valve group (37) for the unloading cylinder.

2. The hydraulic system for a powder forming press according to claim 1, characterized in that, The oil tank (1) is connected to the oil cooler (12) through two pipes. The oil outlet pipe is located at the end of the oil tank (1) and a second oil suction filter (5) is installed. An oil pump is also installed on the oil outlet pipe and is located in the cabinet where the oil cooler (12) is located.

3. The hydraulic system for a powder forming press according to claim 1, characterized in that, The high-performance proportional pressure reducing valve (22) is connected to the oil outlet passage of the second oil circuit block (21), and the high-performance proportional pressure reducing valve (22) is connected to the third oil circuit block (26). The oil return passage of the third oil circuit block (26) is connected to the oil return passage in the second oil circuit block (21).

4. The hydraulic system for a powder forming press according to claim 3, characterized in that, The third oil circuit block (26) is superimposed with a balance valve (27), another plug-in check valve (17), another first plug-in solenoid ball valve (20), a first hydraulic check valve (25) and a third solenoid directional valve (24). The balance valve (27) is connected to the fourth oil circuit block (28) through a pipeline. The fourth oil circuit block (28) is equipped with two first plug-in solenoid ball valves (20), a plug-in throttle valve (29) and an accumulator (40). The fourth oil circuit block (28) outputs to the foaming machine spray gun through a pipeline. A pressure sensor (15) is installed on the pipeline. The oil return port of the foaming machine spray gun is connected to the oil return port of the balance valve (27) through a pipeline. Pressure test connectors (16) are installed on the oil outlet and oil return pipelines between the balance valve (27) and the fourth oil circuit block (28).

5. The hydraulic system for a powder forming press according to claim 3, characterized in that, A second solenoid directional valve (31) is also installed on the second oil circuit block (21). The second solenoid directional valve (31) is connected to the second hydraulic control check valve (32). The second hydraulic control check valve (32) is connected to the return oil circuit of the fifth oil circuit block (33). The second solenoid directional valve (31) is connected to the inlet oil circuit of the fifth oil circuit block (33). The inlet oil circuit of the second solenoid directional valve (31) is connected to the inlet oil circuit of the second oil circuit block (21). The return oil circuit of the second solenoid directional valve (31) is connected to the return oil circuit of the second oil circuit block (21). A pressure tester (16) is installed on the oil circuit between the second solenoid directional valve (31) and the fifth oil circuit block (33).

6. The hydraulic system for a powder forming press according to claim 5, characterized in that, The fifth oil circuit block (33) is connected to another accumulator (40). A pressure sensor (15) is installed in the oil inlet of the fifth oil circuit block (33). A pressure sensor (15) is installed between the accumulator (40) and the oil return of the fifth oil circuit block (33). A throttle valve (36), an overflow valve (35) and a second-insert solenoid ball valve (34) are also installed in the oil return of the fifth oil circuit block (33). The oil inlet and oil return of the fifth oil circuit block (33) are connected to another set of foaming machine spray guns.

7. The hydraulic system for a powder forming press according to claim 3, characterized in that, The second oil circuit block (21) is also equipped with a buffer valve group and a material return cylinder reserved valve group (37). The buffer valve group includes a stacked pressure reducing valve (41). The stacked pressure reducing valve (41) is equipped with a pressure gauge (39) and a first solenoid directional valve (30). The oil inlet and return lines in the stacked pressure reducing valve (41) are connected. The stacked pressure reducing valve (41) controls the oil inlet and return through the valve core. The oil inlet and return ports of the first solenoid directional valve (30) are respectively connected to the pressure test connector (16).

Images