Air supply device and control system applied to large printing equipment

Abstract

This invention relates to positive pressure air supply equipment, and more particularly to an air supply device and control system for large printing equipment. The device includes a compressor impeller installed within a compressor housing, which is connected to an inlet pipe and an outlet pipe; a motor shaft with the compressor impeller connected to its end, and both ends of the motor shaft mounted within a motor housing via air bearings; a motor bracket with the motor shaft connected to its middle section, and a rotor core mounted outside the motor bracket; wherein the motor shaft has a main cooling channel in its middle section, and an air guide pipe is installed between the end of the main cooling channel and the outlet pipe; the main cooling channel is connected to a secondary cooling channel, which is located within the motor bracket, with its other end situated between the motor bracket and the rotor core. This invention improves the heat dissipation efficiency of the air supply device and extends the service life of the motor.

Description

Technical Field

[0001] This invention relates to positive pressure air supply equipment, and more particularly to an air supply device and control system for use in large printing equipment. Background Technology

[0002] Positive pressure air supply equipment is a compressed air supply device specifically designed for large-scale printing production lines. Its main function is to provide a stable air source with a large flow rate and low pressure for the printing process. It is widely used in key processes such as paper conveying, paper splitting, drying, and pneumatic control. In the traditional model, most printing workshops adopt a solution where each piece of equipment has its own independent air supply device. Each machine is equipped with its own air compressor and air tank. Although this can ensure basic air supply, it has problems such as repeated investment in equipment, cumulative energy consumption, decentralized maintenance, and concentrated noise, resulting in higher overall operating costs.

[0003] With increasingly stringent requirements for energy conservation and emission reduction, the printing industry is gradually shifting from decentralized to centralized air supply. By establishing a central positive pressure air supply station, utilizing variable frequency air compressors and intelligent pipeline systems to uniformly prepare and distribute compressed air, the output can be dynamically adjusted according to actual air demand, effectively reducing no-load losses. Centralized air supply not only significantly reduces overall power consumption and equipment footprint but also enables unified filtration and dehumidification, stabilizing air pressure and quality, thereby improving printing accuracy and production efficiency. It has become an important direction for the upgrading of pneumatic systems in modern printing enterprises. For example, a prior application with publication number CN103671222A discloses a novel electric compressor structure that uses air bearings to reduce rotor resistance and increase motor speed, thereby obtaining a large flow rate of gas. While air bearings can reduce rotor rotational resistance, the high heat generated by the motor at high speeds makes it difficult to further increase the motor's compressed air power.

[0004] Therefore, those skilled in the art are dedicated to developing an air supply device and control system for use in large-scale printing equipment, to improve the heat dissipation efficiency of the air supply device and extend the service life of the motor. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide an air supply device and control system for use in large printing equipment, thereby improving the heat dissipation efficiency of the air supply device and extending the service life of the motor.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A gas supply device applied to large-scale printing equipment, comprising... A compressor impeller is installed inside a compressor housing, which is connected to an inlet pipe and an outlet pipe. The motor shaft has the air impeller connected to its end, and both ends of the motor shaft are mounted inside the motor housing via air bearings. A motor bracket, wherein the middle part of the motor shaft is connected to the motor bracket, and a rotor core is installed on the outside of the motor bracket; The motor shaft has a main cooling channel in the middle, and an air guide pipe is installed between the end of the main cooling channel and the air outlet pipe. The main cooling channel is connected to a sub-cooling channel, which is located inside the motor bracket. The other end of the sub-cooling channel is located between the motor bracket and the rotor core.

[0007] The beneficial effects of the above scheme are as follows: By introducing the high-pressure gas generated by the compressor impeller into the main cooling channel in the middle of the motor shaft through the air guide pipe, and then delivering it to the space between the motor support and the rotor core through the branch cooling channels, the gas output by the compressor itself can be directly used as the cooling medium inside the motor. The faster the compressor impeller rotates, the greater the flow rate and pressure of the compressed air, and the greater the flow rate of cooling air entering the motor, thus adapting to the cooling rate of the motor. At the same time, the high-pressure gas provides gas with a certain pressure to the air bearing, which is beneficial for the suspension support of the air bearing. Active heat dissipation of the core heat-generating components of the motor can be achieved without the need for additional independent cooling equipment. This effectively reduces the temperature of key parts such as the motor shaft, motor support, and rotor core under high-speed operation, reduces the resistance generated when the rotor rotates, improves the overall heat dissipation efficiency of the air supply device, and thus extends the service life of the motor.

[0008] Based on the above technical solution, the present invention can be further improved as follows.

[0009] Furthermore, the rotor core is mounted on the motor bracket at both ends via a first end plate and a second end plate, respectively. A cooling channel is provided on the rotor core, and a sidewall cooling channel is formed between the motor bracket and the rotor core. The first end plate has a reversing groove, the two ends of which are respectively connected to the branch cooling channel and the side wall cooling channel. The second end plate is provided with an annular cooling channel, which is connected to the branch cooling channel.

[0010] The beneficial effects of adopting the above-mentioned further scheme are as follows: by setting a first end plate and a second end plate at both ends of the rotor core, opening a cooling channel on the rotor core, forming a side wall cooling channel between the motor support and the rotor core, and using the commutation slot on the first end plate to connect the cooling channel with the side wall cooling channel, and the annular cooling channel on the second end plate to connect the cooling channel, the cooling gas can form a multi-path circulation flow between the rotor support, the side wall cooling channel, the first end plate, the inside of the rotor core, and the second end plate, thereby extending the cooling path and improving the overall cooling efficiency inside the motor.

[0011] Furthermore, the second end plate is also provided with an air outlet, which faces the air bearing near the end of the compressor impeller.

[0012] The beneficial effects of adopting the above-mentioned further solution are: by setting an air outlet on the second end plate that faces the air bearing near the compressor impeller end, the cooling gas delivered by the cooling circuit can be directly and directionally sprayed onto the front air bearing. This not only provides the necessary pressurized gas to support the suspension of the front bearing, but also helps to cool the front air bearing. Furthermore, the cooling gas inside the motor is discharged after being collected by the front air bearing.

[0013] Furthermore, there is an installation gap between the motor shaft end and the motor housing. The motor shaft end is connected to the motor housing through the air bearing. Part of the cooling gas ejected through the air guide pipe enters the main cooling channel, and part of it enters the motor housing through the air bearing. The motor bracket is also equipped with weight-reducing and ventilation holes.

[0014] The beneficial effects of adopting the above-mentioned further solution are as follows: the motor shaft end is connected to the inside of the motor housing through an air bearing, so that the motor shaft is set inside the air bearing. The gas ejected from the duct is sprayed into the air bearing. Part of it enters the main cooling channel, and part of it enters the motor housing through the air bearing. It is not only used to provide air source to the rear air bearing and the main cooling channel, but also allows part of the air source to enter the inside of the rotor support to cool the rotor support, and flows to the front air bearing through the weight reduction vent, thereby improving the overall cooling efficiency of the motor.

[0015] Furthermore, an air collector is installed outside the motor housing. The air collector is located outside the motor shaft and its end is close to the air compressor housing. The motor shaft located outside the motor housing has a main air intake and at least one branch air intake on the motor shaft. The main air intake communicates with the branch air intake, and the end of the branch air intake is located inside the air collector. The main air intake is also vertically connected to multiple outlet air intakes, the ends of which are located on the air intake side of the compressor impeller.

[0016] The beneficial effects of adopting the above-mentioned further solution are: the gas collector is used to collect the gas discharged from the front air bearing. The end of the gas collector is close to the compressor housing, so that the gas accumulates in the gas collector and generates a lateral thrust on the end face of the compressor impeller, which balances part of the lateral thrust generated by the compressor impeller and reduces the vibration and jolt of the compressor impeller. The gas collected in the gas collector enters the main air intake through the branch air intake and is then discharged to the air intake end of the compressor impeller through the branch air intake. This not only cools the front motor shaft and the inside of the compressor impeller, but also allows the main air intake to be vertically connected to multiple branch air intakes, so that the cooled gas can be discharged evenly through multiple branch air intakes. The vertical connection between the main intake duct and multiple outlet ducts causes a sharp change in the direction of gas flow. The impact force generated by the gas acts on the end of the main intake duct, exerting a lateral force on the motor shaft and reducing the vibration of the motor shaft.

[0017] Furthermore, a purification device and an electrically controlled valve are installed on the air duct, and both the purification device and the electrically controlled valve are electrically connected to a control module.

[0018] The beneficial effects of adopting the above-mentioned further solution are as follows: Installing a purification device and an electrically controlled valve on the air duct and electrically connecting the purification device and the electrically controlled valve to the control module allows the cooling gas entering the internal cooling channel of the motor to be pre-filtered and purified, effectively preventing dust, particles and other pollutants from entering the main cooling channel, sub-cooling channel and air bearing and causing blockage or wear, thereby ensuring the smooth flow of the cooling system and the cleanliness and operating accuracy of the air bearing. At the same time, the electrically controlled valve can automatically adjust the on / off and flow of the cooling gas according to the control command, realizing intelligent control of the cooling process.

[0019] A control system for large-scale printing equipment includes, as described above, a gas supply device for large-scale printing equipment, comprising... Pressure detection module, used to detect the gas pressure inside the gas storage tank; A control module, electrically connected to the pressure detection module, is used to acquire the gas pressure inside the gas storage tank and compare it with a preset pressure setting value. The frequency converter is electrically connected to the control module and is used to output a corresponding drive current frequency to the motor to adjust the motor speed according to the comparison result.

[0020] The beneficial effects of adopting the above-mentioned further solution are as follows: the pressure detection module detects the gas pressure in the gas storage tank in real time, the control module compares the measured pressure with the preset pressure setting value, and the frequency converter outputs the corresponding drive current frequency according to the comparison result to adjust the motor speed. This enables the gas supply system to automatically adjust the compressed gas power and output gas volume according to the actual gas demand of the large printing equipment, thereby realizing closed-loop automatic control of the gas supply pressure, avoiding energy waste caused by motor idling or overpressure operation, and reducing overall energy consumption and operating costs.

[0021] Furthermore, it also includes a human-machine interface, which is electrically connected to the control module via a communication bus; The human-computer interaction interface includes a touch screen and a data storage unit; The touch screen is used for users to set the pressure setting value and to display the current gas pressure, motor operating frequency, motor operating temperature and system operating status in real time; The data storage unit is used to record historical operating parameters and alarm events.

[0022] The beneficial effects of adopting the above-mentioned further solution are as follows: By setting up a human-machine interface electrically connected to the control module via a communication bus, and configuring a touch screen and data storage unit, operators can intuitively and conveniently set pressure parameters and view the current gas pressure, motor operating frequency, working temperature and system operating status in real time through the touch screen. This enables comprehensive monitoring and convenient operation of the gas supply device. At the same time, the data storage unit's recording of historical operating parameters and alarm events facilitates subsequent fault tracing, operating trend analysis and maintenance plan formulation, thereby improving the digitalization level of equipment management and operation and maintenance efficiency.

[0023] Furthermore, it also includes an alarm unit, which is electrically connected to the control module. The control module is also electrically connected to an electric control valve and a filter removal device. The filter removal device is equipped with a differential pressure sensor or a filter life detector to monitor the working status of the filter removal device in real time. When the impurity removal device experiences abnormal conditions such as filter element blockage, excessive internal differential pressure, or expired filter element life, the differential pressure sensor or filter element life detector will feed back the abnormal signal to the control module. After the control module determines that the impurity removal device is abnormal, it sends a shutdown command to the electronic control valve to cut off the gas passage in the air duct and maintains the alarm status.

[0024] The beneficial effects of adopting the above-mentioned further solution are as follows: by setting an alarm unit electrically connected to the control module, and configuring a differential pressure sensor or filter life detector in the impurity removal device to monitor its working status in real time, the system can promptly obtain abnormal signals when abnormal situations such as filter blockage, excessive internal differential pressure, or filter life expiration occur. Based on this, the control module automatically sends a shut-off command to the electronic control valve to cut off the gas passage of the air duct and maintains the alarm status. Thus, when the impurity removal device fails, it immediately blocks the path of impurities into the internal cooling channel of the motor, effectively preventing contaminants from damaging the air bearing and internal components of the motor. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the air supply device structure applied to a large printing equipment according to a specific embodiment of the present invention; Figure 2 This is a schematic diagram of the internal structure of an air supply device applied to a large printing equipment according to a specific embodiment of the present invention; Figure 3 This is a schematic diagram of the planar structure of the motor and compressor impeller according to a specific embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the air intake, main air intake, branch air intake and outlet air intake according to a specific embodiment of the present invention; Figure 5 This is a structural diagram of a control system applied to a large-scale printing equipment according to a specific embodiment of the present invention.

[0026] The attached diagram lists the components represented by each number as follows: 1. Compressor impeller; 2. Compressor housing; 3. Inlet pipe; 4. Outlet pipe; 5. Motor shaft; 6. Air bearing; 7. Motor housing; 8. Motor bracket; 9. Rotor core; 10. Main cooling channel; 11. Air guide pipe; 12. Branch cooling channel; 14. Sub-branch cooling channel; 15. Side wall cooling channel; 16. Reversing slot; 17. Annular cooling channel; 18. Outlet duct; 19. Air collector; 20. Main inlet duct; 21. Sub-inlet duct; 22. Outlet duct; 23. Impurity removal device; 24. Electrically controlled valve; 25. First end plate; 26. Second end plate; 27. Control module; 28. Pressure detection module; 29. ​​Frequency converter; 30. Human-machine interface; 31. Alarm unit. Detailed Implementation

[0027] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0028] In the description of this invention, it should be understood that the terms "center," "length," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "inner," "outer," "circumferential," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the system or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0029] In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0030] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0031] like Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, an air supply device for large printing equipment includes a compressor impeller 1. The compressor impeller 1 has multiple arc-shaped blades evenly distributed along the circumference and is installed in the flow channel inside the compressor housing 2. The compressor housing 2 adopts a volute structure and has an inlet pipe 3 and an outlet pipe 4 sealed to its two sides respectively. A filter is installed on the inlet pipe 3 and is used to introduce outside air into the compressor housing 2. The outlet pipe 4 is used to discharge the high-pressure gas compressed by the compressor impeller 1. The motor shaft 5 is a stepped shaft with a hollow channel along its axial direction. The ends of the motor shaft 5 are fixedly connected to the central hub of the air impeller 1 by key connection or interference fit to transmit rotational torque. The outer circumferential surfaces of the two ends of the motor shaft 5 are respectively installed in the bearing seats at both ends of the motor housing 7 by air bearings 6. The air bearings 6 are radial air dynamic pressure bearings, which use the high-pressure gas introduced to form an air film between the motor shaft 5 and the bearing sleeve to support the high-speed rotation of the motor shaft 5 and reduce friction loss. The motor bracket 8 is fixedly sleeved on the outer circumference of the middle part of the motor shaft 5 by interference fit. The rotor core 9, which is made of multiple layers of silicon steel sheets, is installed on the outer circumference of the motor bracket 8. The rotor core 9 corresponds to the stator winding on the inner wall of the motor housing 7 to form a motor drive structure. The motor shaft 5 has a main cooling channel 10 along its axial direction in the middle. The main cooling channel 10 is an axial blind hole that does not penetrate the middle of the motor shaft 5. A guide pipe 11 is installed between the end of the main cooling channel 10 away from the compressor impeller 1 and the outlet pipe 4. The end of the guide pipe 11 has a nozzle-type structure. The guide pipe 11 is non-contact with the motor housing 7. The center line of the guide pipe 11 is on the same straight line as the center line of the main cooling channel 10. The guide pipe 11 is used to guide a part of the high-pressure compressed air in the outlet pipe 4 into the main cooling channel 10. A branch cooling channel 12 is connected to the middle of the main cooling channel 10. The branch cooling channel 12 is a radial through hole opened inside the motor bracket 8. The branch cooling channel 12 is set inside the motor bracket 8 and its other end is located in the gap between the outer circumferential surface of the motor bracket 8 and the inner circumferential surface of the rotor core 9, so that a part of the high-pressure gas drawn from the outlet pipe 4 can pass through it. After entering the main cooling channel 10 through the air guide pipe 11, the air is then diverted through the branch cooling channel 12 and directly delivered to the gap area between the motor bracket 8 and the rotor core 9. This utilizes the high-pressure gas output by the air compressor itself as a cooling medium to actively cool the heat-generating components inside the motor. The higher the speed of the air compressor impeller 1, the greater the flow rate and pressure of the compressed air, and the flow rate of the cooling gas entering the motor increases accordingly to match the heat dissipation requirements of the motor. At the same time, the high-pressure gas provides a certain pressure air source to the air bearing 6 to facilitate the suspension support of the air bearing 6. Without the need for an additional independent cooling fan or coolant circulation system, continuous heat dissipation can be achieved for key heat-generating parts such as the motor shaft 5, motor bracket 8, and rotor core 9. This effectively reduces the temperature rise inside the motor under high-speed operation, improves the overall heat dissipation efficiency of the air supply device, and extends the service life of the motor.

[0032] like Figure 1 , Figure 2 and Figure 3As shown, in some embodiments, the two ends of the rotor core 9 are respectively mounted on the motor bracket 8 via a first end plate 25 and a second end plate 26. The first end plate 25 and the second end plate 26 are both annular plate structures and are respectively press-fitted and fixed on the two end faces of the motor bracket 8. The two end faces of the rotor core 9 abut against and are positioned with the inner end faces of the first end plate 25 and the second end plate 26 respectively. A screw is also provided between the first end plate 25, the rotor core 9 and the second end plate 26, and is locked by a nut so that the first end plate 25 and the second end plate 26 clamp the rotor core 9. Multiple circumferentially distributed cooling channels 14 are formed along the axial direction of the rotor core 9. The cooling channels 14 are axial through holes penetrating the silicon steel sheets of the rotor core 9. A sidewall cooling channel 15 is formed between the outer circumferential surface of the motor bracket 8 and the inner circumferential surface of the rotor core 9. A reversing groove 16 is formed on the end face of the first end plate 25. The reversing groove 16 is a U-shaped groove or an arc-shaped groove. The two ends of the reversing groove 16 are respectively connected to the ends of the cooling channels 14 and the ends of the sidewall cooling channels 15. An annular cooling channel 17 is formed on the end face of the second end plate 26. The annular cooling channel 17 is circumferential around the center of the second end plate 26. The annular groove on the axis is connected to the other end of the branch cooling channel 14, so that the cooling gas flows out from the branch cooling channel 12 and enters the side wall cooling channel 15, and then flows into the branch cooling channel 14 through the reversing groove 16 on the first end plate 25. Subsequently, it flows through the branch cooling channel 14 to the annular cooling channel 17 on the second end plate 26 and gathers, thereby forming a multi-path circulating cooling circuit between the rotor core 9, the motor bracket 8, the first end plate 25 and the second end plate 26, effectively extending the flow path and heat exchange time of the cooling gas inside the motor and improving the overall cooling efficiency inside the motor.

[0033] The second end plate 26 is also provided with an air outlet 18, which is an inclined through hole on the second end plate 26. The air outlet of the air outlet 18 faces the air bearing 6 near the end of the compressor impeller 1, so that the cooling gas delivered by the cooling circuit can be directly and directionally sprayed to the front air bearing 6. This not only provides the necessary pressurized gas to the front air bearing 6 to maintain its suspension support function, but also helps to cool the bearing sleeve of the front air bearing 6 and the end of the motor shaft 5. Furthermore, the cooling gas inside the motor can be smoothly discharged to the outside of the motor after being collected by the front air bearing 6.

[0034] like Figure 3As shown, in another embodiment, there is an installation gap between the end of the motor shaft 5 and the motor housing 7. The installation gap is an annular gap between the outer circumferential surface of the end of the motor shaft 5 and the inner bore surface of the bearing seat of the motor housing 7. The end of the motor shaft 5 is connected to the motor housing 7 through an air bearing 6. Part of the cooling gas ejected through the air guide pipe 11 enters the main cooling channel 10, and the other part enters the motor housing 7 through the air inlet of the air bearing 6. The gas distribution structure of the air bearing 6 allows the incoming cooling gas to simultaneously supply the rear air bearing 6 and the main cooling channel 10. The air source also allows some air to enter the inner side of the motor bracket 8 to cool the inner circumferential surface of the motor bracket 8 and the middle outer surface of the motor shaft 5. The motor bracket 8 is also provided with multiple circumferentially distributed weight-reducing vent holes. The weight-reducing vent holes are through holes that penetrate the wall thickness of the motor bracket 8. They are used to reduce the rotating mass of the motor bracket 8 to reduce the moment of inertia, and also allow the cooling gas flowing from the inner side of the motor bracket 8 to flow through the weight-reducing vent holes to the front air bearing 6, thereby further improving the overall cooling efficiency of the motor and optimizing the distribution of gas inside the motor.

[0035] In this embodiment, an air collector 19 is fixedly installed outside the motor housing 7. The air collector 19 is a sleeve-shaped structure located outside the motor shaft 5. One end of the air collector 19 is welded and fixed to the outer wall of the motor housing 7, and the other end of the air collector 19 is close to the end face of the compressor housing 2 but does not contact it. A main air intake duct 20 is opened in the middle of the motor shaft 5 outside the motor housing 7 along its axial direction. At least one radially arranged branch air intake duct 21 is also opened on the motor shaft 5. The main air intake duct 20 and the branch air intake duct 21 intersect perpendicularly and communicate with each other inside the motor shaft 5. The outer end opening of the branch air intake duct 21 is located in the inner cavity of the air collector 19, so that the gas collected in the air collector 19 can enter the main air intake duct 20 through the branch air intake duct 21. The main air intake duct 20 is also vertically connected to a plurality of circumferentially distributed outlet air intake ducts 22. The outlet air intake ducts 22 are located from the side wall of the main air intake duct 20. The through-hole is located near the disc on the air intake side of the compressor impeller 1, allowing the gas in the main air intake duct 20 to be evenly discharged to the air intake end of the compressor impeller 1 through multiple outlet air passages 22. This not only cools the end of the front motor shaft 5 and the disc and blade roots inside the compressor impeller 1, but also allows the cooling gas to be evenly discharged through multiple outlet air passages 22 due to the perpendicular connection between the main air intake duct 20 and the multiple outlet air passages 22. At the same time, the perpendicular connection between the main air intake duct 20 and the multiple outlet air passages 22 causes a sharp change in the gas flow direction. The impact force generated by the gas will act on the end of the main air intake duct 20 to generate a lateral force on the motor shaft 5. The lateral force is opposite to the axial thrust generated by the compressor impeller 1 during operation, thereby balancing part of the lateral thrust generated by the compressor impeller 1, reducing the vibration and surge of the compressor impeller 1, and improving the stability of the air supply device.

[0036] like Figure 2 and Figure 3As shown, in one embodiment, a purification device 23 and an electrically controlled valve 24 are installed on the air duct 11. The purification device 23 is a precision filter with a replaceable filter element. It has a multi-stage filtration structure to remove dust, particles and oil mist impurities from the compressed air. The electrically controlled valve 24 is an electromagnetic proportional valve. Both the purification device 23 and the electrically controlled valve 24 are electrically connected to a control module 27 via cables or connectors. The control module 27 is a programmable logic controller or an embedded control unit, which allows the cooling gas entering the internal cooling channel of the motor to be pre-filtered and purified, effectively preventing dust, particles and other pollutants from entering the main cooling channel 10, the sub-cooling channel 12 and the air bearing 6 and causing blockage or wear. This ensures the smooth flow of the cooling system and the cleanliness and operating accuracy of the air bearing 6. At the same time, the electrically controlled valve 24 can automatically adjust the on / off state and flow rate of the cooling gas according to the control command issued by the control module 27, realizing intelligent control and on-demand supply of the cooling process.

[0037] like Figure 5 As shown, in this embodiment, a control system applied to a large printing equipment includes a gas supply device for the large printing equipment as described above, which includes a pressure detection module 28. The pressure detection module 28 is a pressure sensor installed at the outlet of the gas storage tank or on the main gas supply line. The pressure detection module 28 is used to detect the gas pressure in the gas storage tank in real time and convert the pressure signal into an electrical signal. Control module 27 is electrically connected to pressure detection module 28 via shielded cable. Control module 27 is used to obtain the measured value of gas pressure in gas storage tank and perform PID comparison calculation with preset pressure set value. The frequency converter 29 is electrically connected to the control module 27 via a communication cable or analog signal line. The frequency converter 29 is used to output a corresponding drive current frequency to the motor according to the comparison result output by the control module 27 to adjust the motor speed. This enables the gas supply system to automatically adjust the compressed air power and output air volume according to the actual gas demand of the large printing equipment, thereby realizing closed-loop automatic control of the gas supply pressure, avoiding energy waste caused by motor no-load or overpressure operation, and reducing overall energy consumption and operating costs.

[0038] It also includes a human-machine interface 30, which is electrically connected to the control module 27 via communication buses such as RS485, CAN, or industrial Ethernet. The human-machine interface 30 includes a touch screen and a data storage unit. The touch screen is an industrial-grade color LCD touch screen, which allows users to set pressure settings through a graphical interface and display the current gas pressure, motor operating frequency, motor operating temperature, and system operating status in real time. The data storage unit is a built-in solid-state memory or an external memory card, which is used to record historical operating parameters and alarm events in chronological order. This allows operators to intuitively and conveniently set pressure parameters and view the operating status of the gas supply device in real time through the touch screen, thereby achieving comprehensive monitoring and convenient operation of the gas supply device. At the same time, the recording of historical operating parameters and alarm events by the data storage unit facilitates subsequent fault tracing, operating trend analysis, and maintenance plan formulation, improving the digital level of equipment management and operation and maintenance efficiency.

[0039] It also includes an alarm unit 31, which is an audible and visual alarm and is electrically connected to the control module 27. The control module 27 is also electrically connected to the electric control valve 24 and the impurity removal device 23 via a cable. The impurity removal device 23 is equipped with a differential pressure sensor or a filter life detector. The differential pressure sensor is used to detect the gas pressure difference before and after the filter element of the impurity removal device 23 in real time. The filter life detector is used to record the cumulative running time or processed gas volume of the filter element. Both are used to monitor the working status of the impurity removal device 23 in real time. When the impurity removal device 23 experiences abnormal conditions such as filter element blockage, excessive internal differential pressure, or filter element life expiration, the differential pressure sensor or filter life detector will feed back the abnormal signal to the control module 27. After the control module 27 determines that the impurity removal device 23 is abnormal, it sends a shut-off command to the electric control valve 24 to cut off the gas passage in the air guide pipe 11 and maintain the alarm status. In this way, when the impurity removal device 23 fails, it immediately blocks the path of impurities into the internal cooling channel of the motor, effectively preventing contaminants from damaging the air bearing 6 and the internal components of the motor, and ensuring the safe and reliable operation of the air supply device.

[0040] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gas supply device for use in large-scale printing equipment, characterized in that: include A compressor impeller (1) is installed inside a compressor housing (2), which is connected to an inlet pipe (3) and an outlet pipe (4). The motor shaft (5) is connected to the air impeller (1) at one end, and the two ends of the motor shaft (5) are installed in the motor housing (7) through air bearings (6); Motor bracket (8), the middle part of the motor shaft (5) is connected to the motor bracket (8), and a rotor core (9) is installed on the outside of the motor bracket (8). The motor shaft (5) has a main cooling channel (10) in the middle. An air guide pipe (11) is installed between the end of the main cooling channel (10) and the air outlet pipe (4). The main cooling channel (10) is connected to a sub-cooling channel (12). The sub-cooling channel (12) is located in the motor bracket (8). The other end of the sub-cooling channel (12) is located between the motor bracket (8) and the rotor core (9).

2. The air supply device for large-scale printing equipment according to claim 1, characterized in that: The rotor core (9) is mounted on the motor bracket (8) at both ends via a first end plate (25) and a second end plate (26), and a cooling channel (14) is provided on the rotor core (9). A side wall cooling channel (15) is formed between the motor bracket (8) and the rotor core (9). The first end plate (25) has a reversing groove (16), the two ends of which are connected to the branch cooling channel (14) and the side wall cooling channel (15) respectively. The second end plate (26) is provided with an annular cooling channel (17), which is connected to the branch cooling channel (14).

3. The air supply device for large-scale printing equipment according to claim 2, characterized in that: The second end plate (26) is also provided with an air outlet (18), which faces the air bearing (6) near the end of the compressor impeller (1).

4. The air supply device for large-scale printing equipment according to claim 1, characterized in that: There is an installation gap between the end of the motor shaft (5) and the motor housing (7). The end of the motor shaft (5) is connected to the motor housing (7) through the air bearing (6). Part of the cooling gas ejected through the air guide pipe (11) enters the main cooling channel (10), and part of it enters the motor housing (7) through the air bearing (6). The motor bracket (8) is also provided with weight-reducing ventilation holes.

5. The air supply device for large-scale printing equipment according to claim 1, characterized in that: An air manifold (19) is installed outside the motor housing (7). The air manifold (19) is located outside the motor shaft (5) and its end is close to the air compressor housing (2). The motor shaft (5) located outside the motor housing (7) has a main air intake (20) and at least one branch air intake (21) on the motor shaft (5). The main air intake (20) communicates with the branch air intake (21) and the end of the branch air intake (21) is located inside the air manifold (19). The main air intake (20) is also vertically connected to a plurality of outlet air intakes (22), the ends of which are located on the air intake side of the compressor impeller (1).

6. The air supply device for large-scale printing equipment according to claim 1, characterized in that: The air duct (11) is equipped with a cleaning device (23) and an electric control valve (24), and both the cleaning device (23) and the electric control valve (24) are electrically connected to a control module (27).

7. A control system for large-scale printing equipment, comprising an air supply device for large-scale printing equipment as described in any one of claims 1 to 6, characterized in that: include Pressure detection module (28) is used to detect the gas pressure in the gas storage tank; The control module (27) is electrically connected to the pressure detection module (28) and is used to obtain the gas pressure in the gas storage tank and compare it with the preset pressure setting value. The frequency converter (29) is electrically connected to the control module (27) and is used to output the corresponding drive current frequency to the motor according to the comparison result to adjust the motor speed.

8. The control system for large-scale printing equipment according to claim 7, characterized in that: It also includes a human-computer interaction interface (30), which is electrically connected to the control module via a communication bus; The human-computer interaction interface (30) includes a touch screen and a data storage unit; The touch screen is used for users to set the pressure setting value and to display the current gas pressure, motor operating frequency, motor operating temperature and system operating status in real time; The data storage unit is used to record historical operating parameters and alarm events.

9. The control system for large-scale printing equipment according to claim 7, characterized in that: It also includes an alarm unit (31), which is electrically connected to the control module (27). The control module (27) is also electrically connected to an electric control valve (24) and a cleaning device (23). The cleaning device (23) is equipped with a differential pressure sensor or a filter life detector to monitor the working status of the cleaning device (23) in real time. When the impurity removal device (23) experiences abnormal conditions such as filter blockage, excessive internal pressure difference, or filter life expiration, the pressure difference sensor or filter life detector will feed back the abnormal signal to the control module (27). After the control module (27) determines that the impurity removal device is abnormal, it sends a shutdown command to the electric control valve (24) to cut off the gas passage in the air duct and maintain the alarm state.

Images