A pressurizing system and method suitable for heavy-duty grinding and polishing equipment

Abstract

The present invention provides a pressurizing system and method suitable for heavy-duty grinding and polishing equipment, belonging to the field of pressurizing technology for grinding and polishing equipment. The system includes: an air source FRL triplet, a safety one-way valve, a pressure switch, a pilot solenoid valve, a hydraulic one-way throttle valve, a pressure sensor, an air-controlled pressure reducing valve, an electrical proportional valve, an exhaust cleaner, an automatic pipeline exhaust valve, a gas-liquid conversion cylinder and a gas-liquid linkage cylinder; the method includes compressed air input, an electrical proportional valve and an air-controlled pressure reducing valve to control the pressure value, and gas-liquid conversion drives the upper plate to rise and fall. The present invention adopts a large-diameter cylinder and a large-diameter pipeline, which is suitable for heavy-duty grinding and polishing machines.

Description

Technical Field

[0001] The invention relates to the technical field of pressurizing grinding and polishing equipment, and in particular to a pressurizing system and method suitable for heavy-duty grinding and polishing equipment. Background Art

[0002] Ordinary grinding and polishing machines generally use cylinders and are controlled by air pressure. Due to the compressibility of air, the movement speed of the cylinder is easily affected by the load, especially when moving at low speed, the stability is poor. Hydraulic control is generally used in high-power and high-load output occasions. It works smoothly, especially when running slowly and at low speed. However, the control difficulty is higher than that of air pressure, and the maintenance requirements are also higher. Gas-liquid conversion linkage control combines the advantages of pneumatic and hydraulic control. It has both the rapidity and low cost of pneumatic control and the load capacity and high precision of hydraulic control. By converting pneumatic transmission into hydraulic transmission through a gas-liquid conversion cylinder, a more stable motion control effect can be obtained. Gas-liquid conversion control can flexibly adjust the ratio of air pressure and hydraulic pressure as needed to meet different control requirements. Gas-liquid linkage cylinders usually include a pneumatic part and a hydraulic part. The pneumatic part is responsible for providing power and control signals, while the hydraulic part uses hydraulic oil to transmit and amplify force. In this cylinder, gas pressure is used to drive hydraulic oil, which in turn drives the piston to move. Due to the incompressibility of hydraulic oil, stable output force and speed can be maintained even at low speeds. The gas-liquid conversion linkage control can accurately control the movement of the piston through pressure sensor feedback, thereby achieving high-precision motion control. The gas-liquid conversion linkage control structure is relatively simple and easy to maintain.

[0003] The prior art discloses a pressurizing system suitable for a grinding and polishing machine, such as the invention patent with publication number CN112145488A, which discloses a high-precision gas-liquid linkage drive system for a double-sided machine. The patent also uses gas-liquid conversion linkage control to achieve the rapid descent, slow descent, slow rise and rapid rise of the upper plate of the grinding and polishing machine. Advantages: ① It is more stable during the slow descent of the upper plate, and can press the surface of the workpiece at a very slow speed / smaller plate pressure (avoid crushing the workpiece); ② When processing the workpiece, the medium (oil, gas) in the lower chamber of the cylinder will press the piston upward to indirectly offset the pressure of the upper plate on the workpiece. The machine with oil as the medium is more stable than the machine with gas as the medium, and the precision of the processed workpiece is higher. However, the patent is suitable for small machines, and uses gas-liquid conversion linkage to control the stability of processing. It is suitable for processing ultra-thin optical and semiconductor wafers with a processing pressure below 200kg. For heavy machines with a processing pressure of 3000kg-5000kg, the system provided by the patent is not applicable. To this end, the invention provides a pressurization system and method suitable for heavy-duty grinding and polishing equipment. Summary of the invention

[0004] The object of the present invention is to provide a pressurizing system and method suitable for heavy-duty grinding and polishing equipment. In order to solve the above technical problems, the object of the present invention is achieved as follows:

[0005] A pressurizing system suitable for heavy-duty grinding and polishing equipment, including: an air source FRL triplet, a safety one-way valve, a pressure switch, a pilot solenoid valve, a hydraulic one-way throttle valve, a pressure sensor, an air-controlled pressure reducing valve, an electric proportional valve, an exhaust cleaner, an automatic pipeline exhaust valve, an air-liquid conversion cylinder and an air-liquid linkage cylinder;

[0006] The gas-liquid conversion cylinder is connected to the gas source through a pipeline; the gas source FRL triplet is arranged on the pipeline; the safety one-way valve is arranged on the pipeline and is located on the side of the gas source FRL triplet away from the gas source; the pressure switch is arranged on the pipeline and is located between the gas source FRL triplet and the safety one-way valve;

[0007] The gas-liquid linkage cylinder is connected to the gas-liquid conversion cylinder through a hydraulic oil delivery pipe; the pilot solenoid valves are two in number and are arranged at intervals on the hydraulic oil delivery pipe; the hydraulic one-way throttle valve is arranged in parallel with one of the pilot solenoid valves on the hydraulic oil delivery pipe;

[0008] The air-controlled pressure reducing valve is arranged on the pipeline and is located between the safety one-way valve and the gas-liquid conversion cylinder; the electric proportional valve is arranged on the air pipe connected to the pipeline, and its output port is connected to the control port of the air-controlled pressure reducing valve; the pressure sensor is arranged on the pipeline and is located between the air-controlled pressure reducing valve and the gas-liquid conversion cylinder; the exhaust cleaner is arranged on the air-controlled pressure reducing valve and the gas-liquid linkage cylinder;

[0009] The pipeline automatic exhaust valve is arranged on the hydraulic oil delivery pipe.

[0010] On the basis of the above scheme and as a preferred scheme of the above scheme, the cylinder diameter of the gas-liquid conversion cylinder is 700-1000mm; the cylinder diameter of the gas-liquid linkage cylinder is 700-1000mm.

[0011] On the basis of the above scheme and as a preferred scheme of the above scheme, the diameter of the pipeline is 25.4 mm; the diameter of the hydraulic oil delivery pipe is 25.4 mm; and the diameter of the air pipe is 10 mm.

[0012] On the basis of the above scheme and as a preferred scheme of the above scheme, the pipeline is a hard pipe; the hydraulic oil delivery pipe is a hydraulic explosion-proof pipe.

[0013] A pressurization method suitable for heavy-duty grinding and polishing equipment comprises the following steps:

[0014] S1: The compressed air generated by the air source passes through the air source FRL triplex, safety check valve and pressure switch, and then through the large-diameter pipeline to the large-flow air-controlled pressure reducing valve. At the same time, the air pipe connected to the pipeline is used to pass the air to the electric proportional valve;

[0015] S2: The output port of the electric proportional valve is connected to the control port of the large-flow pneumatic pressure reducing valve. The PLC controls the electric proportional valve to output the specified air pressure. The large-flow pneumatic pressure reducing valve controls the opening according to the output specified air pressure to output the required air pressure to the large-diameter air-liquid conversion cylinder.

[0016] S3: The large-bore gas-liquid conversion cylinder converts the air pressure into hydraulic pressure. The hydraulic oil is transmitted to the large-bore gas-liquid linkage cylinder through the pilot solenoid valves SV1 and SV2 installed on the large-flow flange. The large-bore gas-liquid linkage cylinder outputs pressure to control the lifting and pressurization and decompression actions of the upper plate of the heavy-duty grinding and polishing machine.

[0017] On the basis of the above scheme and as a preferred scheme of the above scheme, the method of PLC controlling the electrical proportional valve in step S2 includes: disconnecting the large-flow gas-controlled pressure reducing valve after keeping the upper disk of the grinding and polishing machine stationary, detecting the air pressure p in the pipeline and the large-diameter gas-liquid conversion cylinder by a pressure sensor, feeding back the detected air pressure p to the PLC, calculating the pressure value in the large-diameter gas-liquid conversion cylinder by the pressure formula F=ps, and calculating the weight of the upper disk of the grinding and polishing machine from the pressure value; the PLC controls the electrical proportional valve to output a specified air pressure according to the weight of the upper disk of the grinding and polishing machine, and the large-flow gas-controlled pressure reducing valve controls its opening according to the specified air pressure to change the pressure value in the large-diameter gas-liquid conversion cylinder, thereby lifting and lowering the upper disk of the grinding and polishing machine and increasing and decreasing the pressure.

[0018] On the basis of the above scheme and as a preferred scheme of the above scheme, when the upper plate of the grinding and polishing machine rises: the large-flow gas-controlled pressure reducing valve maintains a large opening, so that the gas pressure in the large-diameter gas-liquid conversion cylinder increases, the gas pressure is converted into hydraulic pressure, and the hydraulic oil flows from the lower port of the large-diameter gas-liquid conversion cylinder through the pilot solenoid valves SV1 and SV2 installed on the opened large-flow flange to the lower port of the large-diameter gas-liquid linkage cylinder, the generated hydraulic pressure is greater than the dead weight of the upper plate, the piston rod of the large-diameter gas-liquid linkage cylinder moves upward, and the upper plate rises; the larger the opening of the large-flow gas-controlled pressure reducing valve, the faster it rises;

[0019] When the upper plate of the grinding and polishing machine descends rapidly: under the action of the deadweight of the upper plate, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to the lower port, and flowing to the lower port of the large-diameter gas-liquid conversion cylinder through the pilot solenoid valves SV1 and SV2 installed on the opened large-flow flange, and the hydraulic pressure is converted into air pressure, and the air pressure is transmitted to the large-flow air-controlled pressure reducing valve through the upper port of the large-diameter gas-liquid conversion cylinder through the pipeline. When the air pressure generated by the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow air-controlled pressure reducing valve, the piston rod of the large-diameter gas-liquid linkage cylinder moves downward, and the upper plate descends. The greater the air pressure difference, the faster the upper plate descends;

[0020] When the upper plate of the grinding and polishing machine slowly descends: under the action of the deadweight of the upper plate, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to the lower port, and flowing to the lower port of the cylinder diameter gas-liquid conversion cylinder through the opened large-flow flange-mounted pilot solenoid valve solenoid valve SV1 and the hydraulic one-way throttle valve, the hydraulic pressure is converted into air pressure, and the air pressure passes through the upper port of the large-diameter gas-liquid conversion cylinder and is transmitted to the large-flow air-controlled pressure reducing valve through the pipeline. When the air pressure generated at the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow air-controlled pressure reducing valve, the piston rod of the large-diameter gas-liquid linkage cylinder moves downward, and the upper plate descends. The smaller the air pressure difference, the slower the upper plate descends.

[0021] The beneficial effects of the present invention are:

[0022] 1. Compared with the pressurization method suitable for light-duty grinding and polishing machines, the cylinder diameters of the gas-liquid conversion cylinder and the hydraulic oil cylinder of the present invention are much larger (850mm in diameter versus 80mm in diameter). The flow diameters of the control components such as the solenoid valve, pneumatic control valve and pipeline used at the same time are much larger. The installation connection method is changed from a hose to a hard pipe and a hydraulic explosion-proof pipe, which can adapt to greater pressures and meet the use of heavy-duty grinding and polishing machines.

[0023] 2. The upper plate of the heavy-duty grinding and polishing machine is very heavy (20 tons), and a large-diameter cylinder is needed to control the lifting action. Compared with pure cylinders, the gas-liquid conversion cylinder has oil as the medium in the lower chamber, which has less friction and is easier to control the lifting speed. Slow descent makes the plate landing effect better.

[0024] 3. Since the processed product is an ultra-large optical workpiece, the pressure during processing can be heavier, so the requirements for fine control of the gas circuit system are relatively low, and the gas circuit structure is simpler. The existing technology requires the use of 5 additional solenoid valves and 3 throttle valves to finely control the air pressure action. The present invention mainly uses the gravity of the upper plate of the machine and the pneumatic pressure reducing valve controlled by the electrical proportional valve to control the lifting action, and does not use the upper port of the gas-liquid linkage cylinder for air intake and exhaust control, but only uses the lower port for air intake and exhaust, which makes installation easier and more costly.

[0025] 4. Multiple safety protections. ① Safety one-way valve, even if the gas source is disconnected, the gas in the pipeline will not escape; ② Pressure switch, monitors the gas line pressure, and alarms and shuts down for protection when it is lower than the set value; ③ Pilot solenoid valve, the pilot gas must be passed first before the solenoid valve can be opened. In extreme cases, if the pipe bursts, the solenoid valve will be locked and the cylinder port will be sealed.

[0026] 5. Use an electric proportional valve to control the air-controlled pressure reducing valve. The prior art uses an electric proportional valve to directly control the air circuit. However, for heavy-duty grinding and polishing machines, the electric proportional valve does not have such a large flow rate and cannot directly control the air pressure input of the cylinder. Therefore, the present invention uses PLC to control the electric proportional valve to precisely output the specified air pressure to precisely control the opening of the large-diameter air-controlled pressure reducing valve, thereby indirectly controlling the air pressure and achieving precise control of a larger flow rate.

[0027] 6. The prior art uses a weighing sensor to directly measure the pressure value output by the cylinder, and then feeds it back to the PLC for pressure feedback adjustment. Since the upper plate of a heavy-duty grinder is very heavy, the use of a weighing sensor will result in reduced accuracy and inaccurate pressure measurement due to range issues. At the same time, the installation size is large and the cost is high. The present invention measures the pressure value of the pipeline air pressure through an air pressure sensor, and feeds it back to the PLC, and then uses the formula F=ps to calculate the pressure in the gas-liquid conversion cylinder, and then pushes the weight of the upper plate based on the pressure. The sensor of this measurement method is small in size, low in cost, simpler in structure, and more reliable.

[0028] 7. Use an exhaust cleaner instead of an ordinary muffler. The exhaust cleaner consists of a filter and a muffler. It can filter the oil mist discharged from the muffler after long-term use to avoid the accumulation of oil stains in the machine body.

[0029] 8. If there is air in the hydraulic oil pipeline, it will cause many hazards. In the prior art, since the cylinder diameter of the air pressure conversion device is small and the hydraulic oil is small, there is no need to consider this situation. However, the cylinder diameter of the air pressure conversion device of the present invention is very large, and an automatic pipeline exhaust valve needs to be added to automatically exhaust the air at the high point of the pipeline to improve the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the pressurization system of the present invention.

[0031] In the figure: 1. Air source FRL triplex; 2. Safety one-way valve; 3. Pressure switch; 4. Pilot solenoid valve; 5. Hydraulic one-way throttle valve; 6. Pressure sensor; 7. Air-controlled pressure reducer; 8. Electric proportional valve; 9. Exhaust cleaner; 10. Pipeline automatic exhaust valve; 11. Air-liquid conversion cylinder; 12. Air-liquid linkage cylinder. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0033] like Figure 1 As shown, a pressurizing system suitable for heavy-duty grinding and polishing equipment includes: an air source FRL triplet 1, a safety one-way valve 2, a pressure switch 3, a pilot solenoid valve 4, a hydraulic one-way throttle valve 5, a pressure sensor 6, an air-controlled pressure reducing valve 7, an electric proportional valve 8, an exhaust cleaner 9, a pipeline automatic exhaust valve 10, a gas-liquid conversion cylinder 11 and a gas-liquid linkage cylinder 12.

[0034] The gas-liquid conversion cylinder 11 is connected to the gas source through a pipeline. The gas source FRL triplet 1 is arranged on the pipeline, and the safety one-way valve 2 is arranged on the pipeline and is located on the side of the gas source FRL triplet 1 away from the gas source. The pressure switch 3 is arranged on the pipeline and is located between the gas source FRL triplet 1 and the safety one-way valve 2.

[0035] The gas-liquid conversion cylinder 11 is a large-diameter gas-liquid conversion cylinder with a diameter of 850 mm. The pipeline is a large-diameter pipeline with a diameter of 25.4 mm. In order to meet the needs of large flow input, the pipeline adopts a combination of a hard pipe and a hydraulic explosion-proof pipe. The hard pipe is a high-strength metal pipe, such as a galvanized pipe, and the hydraulic explosion-proof pipe is a high-strength hose, which is used for the sections of the pipeline that need to be bent or moved.

[0036] The gas-liquid linkage cylinder 12 is connected to the gas-liquid conversion cylinder 11 through a hydraulic oil delivery pipe. There are two pilot solenoid valves 4, which are arranged at intervals on the hydraulic oil delivery pipe. The hydraulic one-way throttle valve 5 is arranged in parallel with one of the pilot solenoid valves 4 on the hydraulic oil delivery pipe. When the pilot solenoid valve 4 is closed and the hydraulic one-way throttle valve 5 is opened, the hydraulic oil passes through the hydraulic one-way throttle valve 5. When the pilot solenoid valve 4 is opened and the hydraulic one-way throttle valve 5 is opened and closed, the hydraulic oil passes through the pilot solenoid valve 4.

[0037] Among them, the hydraulic oil delivery pipe is a large-diameter hydraulic oil delivery pipe with a diameter of 25.4mm. It adopts the same combination of hard pipe and hydraulic explosion-proof pipe as the above-mentioned pipeline to improve its strength and ensure the safety of large-flow hydraulic oil delivery.

[0038] The pilot solenoid valve 4 is a pilot solenoid valve installed with a large flow flange. Conventional solenoid valves 4 cannot meet the installation and transportation requirements of large pipe diameters and large flows. The upper limit of the fluid pressure range of the pilot solenoid valve 4 is relatively high, and it can be installed with a large flow flange, which is easy to install.

[0039] The air-controlled pressure reducing valve 7 is arranged on the pipeline and is located between the safety one-way valve 2 and the gas-liquid conversion cylinder 11. The electric proportional valve 8 is arranged on the air pipe connected to the pipeline, and its output port is connected to the control port of the air-controlled pressure reducing valve 7. The pressure sensor 6 is arranged on the pipeline and is located between the air-controlled pressure reducing valve 7 and the gas-liquid conversion cylinder 11. The exhaust cleaner 9 is arranged on the air-controlled pressure reducing valve 7 and the gas-liquid linkage cylinder 12, which is used to reduce the exhaust sound and filter the oil mist in the exhaust gas to avoid the accumulation of oil stains in the machine. The pipeline automatic exhaust valve 10 is arranged on the hydraulic oil delivery pipe. If there is air in the hydraulic oil pipeline, it will cause many hazards. In this embodiment, since the cylinder diameter of the air pressure conversion device is very large, the pipeline automatic exhaust valve 10 is added to automatically exhaust the air at the high point of the pipeline to improve the safety of the pipeline.

[0040] Since the electric proportional valve 8 does not have such a large flow rate, it cannot meet the air pressure input of the large-diameter cylinder body of this application. In order to accurately control the air pressure input, this embodiment uses PLC to control the electric proportional valve 8 to precisely output a specified relatively small air pressure, and uses the specified small air pressure to precisely control the opening of the large-diameter air-controlled pressure reducing valve 7, thereby controlling the air pressure in the large-diameter pipeline and achieving precise control of large flow. Among them, the diameter of the air pipe is 10mm to adapt to the small flow rate of the electric proportional valve 8.

[0041] Since the upper plate of the grinding machine will gradually lose weight as it is used during grinding, it is necessary to regularly calibrate the input pressure value to ensure the accuracy of the lifting and lowering movement of the upper plate. Therefore, in this embodiment, a pressure sensor 6 is provided on the pipeline. The pressure value of the pipeline air pressure is measured by the air pressure sensor 6, and the analog value is fed back to the PLC. The formula F=ps is used to calculate the pressure in the pipeline and the gas-liquid conversion cylinder 11, and the weight of the upper plate at this time is inferred based on the pressure.

[0042] A pressurization method suitable for heavy-duty grinding and polishing equipment comprises the following steps:

[0043] S1: The compressed air generated by the air source passes through the air source FRL triplex, safety check valve and pressure switch, and then through the large-diameter pipeline to the large-flow air-controlled pressure reducing valve. At the same time, the air pipe connected to the pipeline is used to pass the air to the electric proportional valve;

[0044] S2: The output port of the electric proportional valve is connected to the control port of the large flow air-controlled pressure reducing valve. The PLC controls the electric proportional valve to output the specified air pressure. The large flow air-controlled pressure reducing valve controls the opening according to the output specified air pressure to output the required air pressure to the large cylinder diameter air-liquid conversion cylinder. The PLC controls the output air pressure of the electric proportional valve according to the calibrated value of the pressure sensor.

[0045] S3: The large-bore gas-liquid conversion cylinder converts the air pressure into hydraulic pressure. The hydraulic oil is transmitted to the large-bore gas-liquid linkage cylinder through the pilot solenoid valves SV1 and SV2 installed on the large-flow flange. The large-bore gas-liquid linkage cylinder outputs pressure to control the lifting and pressurization and decompression actions of the upper plate of the heavy-duty grinding and polishing machine.

[0046] Wherein, the method of PLC controlling the electrical proportional valve in step S2 includes: pressure value calibration;

[0047] The pressure value calibration includes: keeping the upper plate of the grinding and polishing machine suspended and still, disconnecting the large-flow gas-controlled pressure reducing valve, using the pressure sensor to detect the air pressure p in the pipeline and the large-bore gas-liquid conversion cylinder, and feeding the detected air pressure p back to the PLC. The PLC calculates the internal pressure value of the pipeline through the pressure formula F=ps, and the weight of the upper plate of the grinding and polishing machine is obtained from the pressure value. The weight of the upper plate is used as the benchmark for this stage. The PLC controls the electrical proportional valve to output the specified air pressure according to the benchmark, and the large-flow gas-controlled pressure reducing valve controls its opening according to the specified air pressure to change the compressed air input (control the air pressure value in the gas-liquid conversion cylinder). When the input is greater than the benchmark weight, the upper plate rises, and when the input is less than the benchmark weight, the upper plate falls. Calibrate once every period of time to ensure the accuracy of the upper plate lifting control.

[0048] Movement process of upper plate:

[0049] When the upper plate of the grinding and polishing machine rises: the large-flow gas-controlled pressure reducing valve maintains a wide opening, which increases the air pressure in the large-diameter gas-liquid conversion cylinder, converts the air pressure into hydraulic pressure, and the hydraulic oil flows from the lower port of the large-diameter gas-liquid conversion cylinder through the open large-flow flange-mounted pilot solenoid valves SV1 and SV2 to the lower port of the large-diameter gas-liquid linkage cylinder. The hydraulic pressure in the gas-liquid linkage cylinder increases, and the generated hydraulic pressure is greater than the deadweight of the upper plate, pushing the piston rod of the large-diameter gas-liquid linkage cylinder upward, driving the upper plate to rise. The larger the opening of the large-flow gas-controlled pressure reducing valve, the higher the input air pressure, and the faster the upper plate rises.

[0050] When the upper plate of the grinding and polishing machine descends rapidly: under the action of the upper plate's own weight, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to the lower port of the gas-liquid linkage cylinder. The hydraulic oil flows to the lower port of the large-diameter gas-liquid conversion cylinder through the open large-flow flange-mounted pilot solenoid valves SV1 and SV2, and the hydraulic pressure is converted into air pressure. The air pressure passes through the upper port of the large-diameter gas-liquid conversion cylinder and is transmitted to the large-flow gas-controlled pressure reducing valve through the pipeline. When the air pressure generated at the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow gas-controlled pressure reducing valve, the compressed air is discharged by the exhaust cleaner, reducing the air pressure in the gas-liquid conversion cylinder, increasing the hydraulic oil, and moving the piston rod of the large-diameter gas-liquid linkage cylinder downward, causing the upper plate to descend. The greater the difference between the air pressure generated at the upper port of the gas-liquid conversion cylinder and the air pressure output by the gas-controlled pressure reducing valve, the faster the upper plate descends.

[0051] When the upper plate of the grinding and polishing machine slowly descends: under the action of the upper plate's own weight, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to its lower port, and the hydraulic oil flows to the lower port of the cylinder-diameter gas-liquid conversion cylinder through the open large-flow flange-mounted pilot solenoid valve solenoid valve SV1 and the hydraulic one-way throttle valve (at this time, the pilot solenoid valve solenoid valve SV2 is closed), and the hydraulic pressure is converted into air pressure, and the air pressure passes through the upper port of the large-diameter gas-liquid conversion cylinder and is transmitted to the large-flow gas-controlled pressure reducing valve through the pipeline. When the air pressure generated at the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow gas-controlled pressure reducing valve, the compressed air is discharged by the exhaust cleaner, the air pressure in the gas-liquid conversion cylinder decreases, the hydraulic oil rises, the piston rod of the large-diameter gas-liquid linkage cylinder moves downward, and the upper plate descends. The smaller the difference between the air pressure generated at the upper port of the gas-liquid conversion cylinder and the air pressure output by the gas-controlled pressure reducing valve, the slower the upper plate descends.

[0052] Pressurization of the upper plate of the grinding and polishing machine: When processing the workpiece, the pressurization action of the upper plate is the same as the slow descent action process of the upper plate. The precise adjustment of the air pressure by the electrical proportional valve and the large-flow air-controlled pressure reducing valve can accurately control the downward output force of the piston rod of the large-diameter air-liquid linkage cylinder, and use the deadweight of the medium-sized upper plate to pressurize the workpiece.

[0053] This application uses a large-diameter gas-liquid conversion cylinder, a gas-liquid linkage cylinder and a large-flow pipe, which can meet the use requirements of the upper plate part of the heavy-duty grinding and polishing machine, and through the gas-liquid linkage and the coordination of various components, precise control of the lifting and lowering of the upper plate part can be achieved, so that the plate landing effect is better.

[0054] Since the heavy upper plate is mainly used to process super-large optical workpieces, the pressure during processing can be relatively heavy, and the requirements for fine control of the gas circuit system are relatively low. The gas circuit structure design is simpler, easy to install and relatively low in cost. The prior art uses 5 additional solenoid valves and 3 throttle valves to finely control the air pressure action. This embodiment uses the gravity of the upper plate of the machine itself and the pneumatic pressure reducing valve controlled by the electrical proportional valve to control the lifting action, with fewer components and a simpler structure.

[0055] The heavy upper plate is heavy and has higher safety requirements. This embodiment adopts multiple safety measures: ① A safety one-way valve can prevent the compressed air in the pipeline from flowing back. Even if the air source is disconnected, the compressed air in the pipeline will not escape, avoiding the loss of pressure and causing the lower plate to drop rapidly and cause harm; ② A pressure switch can monitor the air circuit pressure and alarm and shut down for protection if it is lower than the set value; ③ A pilot solenoid valve is connected to the pipeline through an air pipe. The pilot air must be passed before the solenoid valve can be opened. When the pipeline bursts in an extreme case, the air flowing from the pipeline to the pilot solenoid valve disappears, the pilot solenoid valve will be locked, and the cylinder port will be sealed to prevent the hydraulic oil from flowing quickly.

[0056] Since the electric proportional valve is suitable for relatively small-diameter air pipes, the pipeline in this embodiment has a large diameter of one inch, and the electric proportional valve is not suitable. Therefore, the structure of the electric proportional valve controlling the air-controlled pressure reducing valve is used to control the input of compressed air.

[0057] By measuring the weight of the upper plate at intervals through the pressure sensor and calibrating the input pressure value, the precise control of the upper plate lifting and lowering can be ensured. The prior art uses a weighing sensor to directly measure the weight of the upper plate, but the weight of the upper plate in this embodiment is huge (20t). The use of a weighing sensor will lead to a decrease in accuracy and inaccurate pressure measurement due to the range problem. In addition, the installation size of the weighing sensor will be very large and the cost will be very high.

[0058] This embodiment uses an exhaust cleaner to replace the ordinary muffler. The exhaust cleaner is composed of a filter and a muffler. The prior art only uses a muffler. After long-term use, it cannot handle the exhausted oil mist, which will cause oil stains all over the machine body. Using an exhaust cleaner can solve this problem.

[0059] If there is air in the hydraulic oil pipeline, it will cause many hazards. In the prior art, since the cylinder diameter of the air pressure conversion device is small and the hydraulic oil is also small, this situation is not considered. In this embodiment, since the cylinder diameter of the air pressure conversion device is very large, for safety, an automatic pipeline exhaust valve is added to automatically exhaust the air at the high point of the pipeline.

[0060] The large cylinder diameter of this embodiment requires a large flow rate and a quick response, and multiple inputs can be used. Multiple pneumatic components can be installed in parallel to increase the flow path of the medium.

[0061] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A pressurizing system suitable for heavy-duty grinding and polishing equipment, characterized in that: include: Air source FRL triplex (1), safety check valve (2), pressure switch (3), pilot solenoid valve (4), hydraulic check throttle valve (5), pressure sensor (6), air-controlled pressure reducing valve (7), electric proportional valve (8), exhaust cleaner (9), pipeline automatic exhaust valve (10), air-liquid conversion cylinder (11) and air-liquid linkage cylinder (12); The gas-liquid conversion cylinder (11) is connected to the gas source through a pipeline; the gas source FRL triplet (1) is arranged on the pipeline; the safety one-way valve (2) is arranged on the pipeline and is located on a side of the gas source FRL triplet (1) away from the gas source; the pressure switch (3) is arranged on the pipeline and is located between the gas source FRL triplet (1) and the safety one-way valve (2); The gas-liquid linkage cylinder (12) is connected to the gas-liquid conversion cylinder (11) via a hydraulic oil delivery pipe; the pilot solenoid valves (4) are two in number and are arranged at intervals on the hydraulic oil delivery pipe; the hydraulic one-way throttle valve (5) is arranged in parallel with one of the pilot solenoid valves (4) on the hydraulic oil delivery pipe; The gas-controlled pressure reducing valve (7) is arranged on the pipeline and is located between the safety one-way valve (2) and the gas-liquid conversion cylinder (11); the electric proportional valve (8) is arranged on the air pipe connected to the pipeline, and its output port is connected to the control port of the gas-controlled pressure reducing valve (7); the pressure sensor (6) is arranged on the pipeline and is located between the gas-controlled pressure reducing valve (7) and the gas-liquid conversion cylinder (11); the exhaust cleaner (9) is arranged on the gas-controlled pressure reducing valve (7) and the gas-liquid linkage cylinder (12); The pipeline automatic exhaust valve (10) is arranged on the hydraulic oil delivery pipe.

2. A pressurizing system suitable for heavy-duty grinding and polishing equipment according to claim 1, characterized in that: The cylinder diameter of the gas-liquid conversion cylinder (11) is 700-1000 mm; the cylinder diameter of the gas-liquid linkage cylinder (12) is 700-1000 mm.

3. A pressurizing system suitable for heavy-duty grinding and polishing equipment according to claim 1, characterized in that: The diameter of the pipeline is 25.4 mm; the diameter of the hydraulic oil delivery pipe is 25.4 mm; and the diameter of the air pipe is 10 mm.

4. A pressurizing system suitable for heavy-duty grinding and polishing equipment according to claim 1, characterized in that: The pipeline is a hard pipe; the hydraulic oil delivery pipe is a hydraulic explosion-proof pipe.

5. A pressurization method suitable for heavy-duty grinding and polishing equipment, characterized in that: The following steps are involved: S1: The compressed air generated by the air source passes through the air source FRL triplex, safety check valve and pressure switch, and then through the large-diameter pipeline to the large-flow air-controlled pressure reducing valve. At the same time, the air pipe connected to the pipeline is used to pass the air to the electric proportional valve; S2: The output port of the electric proportional valve is connected to the control port of the large-flow pneumatic pressure reducing valve. The PLC controls the electric proportional valve to output the specified air pressure. The large-flow pneumatic pressure reducing valve controls the opening according to the output specified air pressure to output the required air pressure to the large-diameter air-liquid conversion cylinder. S3: The large-bore gas-liquid conversion cylinder converts the air pressure into hydraulic pressure. The hydraulic oil is transmitted to the large-bore gas-liquid linkage cylinder through the pilot solenoid valves SV1 and SV2 installed on the large-flow flange. The large-bore gas-liquid linkage cylinder outputs pressure to control the lifting and pressurization and decompression actions of the upper plate of the heavy-duty grinding and polishing machine.

6. A pressurizing method suitable for heavy-duty grinding and polishing equipment according to claim 5, characterized in that: The method for PLC controlling the electrical proportional valve in step S2 includes: disconnecting the large-flow pneumatically controlled pressure reducing valve after keeping the upper disk of the grinding and polishing machine stationary, detecting the air pressure p in the pipeline and the large-diameter gas-liquid conversion cylinder by a pressure sensor, feeding back the detected air pressure p to the PLC, calculating the pressure value in the large-diameter gas-liquid conversion cylinder by the pressure formula F=ps, and calculating the weight of the upper disk of the grinding and polishing machine from the pressure value; the PLC controls the electrical proportional valve to output a specified air pressure according to the weight of the upper disk of the grinding and polishing machine, and the large-flow pneumatically controlled pressure reducing valve controls its opening according to the specified air pressure to change the pressure value in the large-diameter gas-liquid conversion cylinder, thereby lifting and lowering the upper disk of the grinding and polishing machine and increasing and decreasing the pressure.

7. A pressurizing method suitable for heavy-duty grinding and polishing equipment according to claim 6, characterized in that: When the upper plate of the grinding and polishing machine rises: the large-flow gas-controlled pressure reducing valve maintains a large opening, so that the gas pressure in the large-diameter gas-liquid conversion cylinder increases, the gas pressure is converted into hydraulic pressure, and the hydraulic oil flows from the lower port of the large-diameter gas-liquid conversion cylinder through the pilot solenoid valves SV1 and SV2 installed on the opened large-flow flange to the lower port of the large-diameter gas-liquid linkage cylinder. The generated hydraulic pressure is greater than the dead weight of the upper plate, and the piston rod of the large-diameter gas-liquid linkage cylinder moves upward, driving the upper plate to rise; the larger the opening of the large-flow gas-controlled pressure reducing valve, the faster it rises; When the upper plate of the grinding and polishing machine descends rapidly: under the action of the deadweight of the upper plate, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to the lower port, and flowing to the lower port of the large-diameter gas-liquid conversion cylinder through the pilot solenoid valves SV1 and SV2 installed on the opened large-flow flange, and the hydraulic pressure is converted into air pressure, and the air pressure is transmitted to the large-flow air-controlled pressure reducing valve through the upper port of the large-diameter gas-liquid conversion cylinder through the pipeline. When the air pressure generated by the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow air-controlled pressure reducing valve, the piston rod of the large-diameter gas-liquid linkage cylinder moves downward, and the upper plate descends. The greater the air pressure difference, the faster the upper plate descends; When the upper plate of the grinding and polishing machine slowly descends: under the action of the deadweight of the upper plate, the piston rod of the large-diameter gas-liquid linkage cylinder will generate a downward force, squeezing the hydraulic oil to the lower port, and flowing to the lower port of the cylinder diameter gas-liquid conversion cylinder through the opened large-flow flange-mounted pilot solenoid valve solenoid valve SV1 and the hydraulic one-way throttle valve, the hydraulic pressure is converted into air pressure, and the air pressure passes through the upper port of the large-diameter gas-liquid conversion cylinder and is transmitted to the large-flow air-controlled pressure reducing valve through the pipeline. When the air pressure generated at the upper port of the large-diameter gas-liquid conversion cylinder is greater than the air pressure output by the large-flow air-controlled pressure reducing valve, the piston rod of the large-diameter gas-liquid linkage cylinder moves downward, and the upper plate descends. The smaller the air pressure difference, the slower the upper plate descends.

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