Urban rail digital display jacking tool and jacking method thereof
The digital jacking fixture for urban rail transit, which utilizes a PLC controller and sensor system in synergy, has solved the problem of difficult adjustment of precast slabs, enabling rapid and precise jacking and horizontal adjustment, and improving the efficiency and accuracy of subway track laying.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA RAILWAY FIRST GROUP CO LTD
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-05
Smart Images
Figure CN122148607A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of track construction technology, and in particular to a digitally displayed jacking tool for urban rail transit and its jacking method. Background Technology
[0002] As a vital component of urban transportation, the subway carries a large volume of passenger traffic. In recent years, with the rapid development of urban rail transit, higher requirements have been placed on the precision of underground track laying and adjustment, as well as on laying efficiency and safety. The track laying precision is related to the smoothness of subway operation, and the adjustment precision of precast slabs and track panels can solve the aforementioned stability issues. Therefore, fine adjustment of precast slabs is required during subway track laying. However, the existing precast slab fine adjustment operations in subway construction use cumbersome lifting tools, making it impossible to control the lifting dimensions. Moreover, the existing precast slab fine adjustment tools cannot achieve horizontal adjustment of the precast slabs, making it difficult to meet the design requirements for precast slab adjustment precision. Therefore, it is necessary to design a digital and intelligent precast slab fine adjustment device that can achieve rapid lifting and horizontal adjustment. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a digital display lifting fixture and lifting method for urban rail transit. The PLC controller receives data transmitted from a displacement sensor, a first pressure sensor, and a second pressure sensor, and controls the opening of proportional electromagnetic directional valves based on the received data. Multiple proportional electromagnetic directional valves work together to achieve vertical adjustment of the precast slab. The differentiated valve core openings of the proportional electromagnetic directional valves corresponding to the two sets of hydraulic cylinders achieve horizontal adjustment of the precast slab, thus solving the problem of difficulty in horizontal adjustment of the precast slab.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is: a digital display lifting fixture for urban rail transit, the lifting fixture including a mobile platform, a control cabinet and a hydraulic oil tank respectively provided at both ends along the length direction of the mobile platform, the hydraulic oil tank being connected to a hydraulic oil pump, the hydraulic oil pump being coaxially connected to a three-phase asynchronous motor, the three-phase asynchronous motor being connected to the control cabinet to facilitate the control cabinet to control the operation of the three-phase asynchronous motor, the hydraulic oil pump being connected to a hydraulic oil pipe through a hydraulic oil circuit to deliver hydraulic oil to the cylinder assembly for lifting the precast slab, the number of the cylinder assembly being multiple, in the non-working state, the cylinder assembly being threadedly connected to the mobile platform through an adjustable base at the bottom, in the working state, the cylinder assembly being placed at the preset lifting point of the precast slab, the top of the cylinder assembly being directly opposite the steel lifting pad at the bottom of the precast slab to facilitate vertical and horizontal adjustment of the precast slab, the cylinder assembly being connected to the control cabinet to facilitate the transmission of the cylinder extension and retraction.
[0005] Preferably, the hydraulic circuit includes a check valve and a valve seat. The inlet of the check valve is connected to the flange of the hydraulic pump, and the outlet of the check valve is connected to the main oil circuit of the valve seat. A valve assembly and a proportional solenoid directional valve are installed on the valve seat. The inlet of each proportional solenoid directional valve is connected to a portion of the oil circuit within the valve assembly, and the outlet of each proportional solenoid directional valve is connected to the quick-connect fitting of the corresponding cylinder assembly via a hydraulic oil pipe. The connector of the proportional solenoid directional valve is connected to the control cabinet for easy command reception.
[0006] Preferably, the reserved interface of the valve group is equipped with an overflow valve, a balance valve and a first pressure sensor. The overflow valve stabilizes the main oil circuit pressure at 45MPa to ensure that the oil supply pressure of each cylinder assembly is consistent. The oil circuit of each cylinder assembly is connected in series with a balance valve to facilitate stable lifting. The first pressure sensor is connected to the main oil circuit.
[0007] Preferably, a second pressure sensor is installed at the branch oil circuit of the cylinder assembly. The second pressure sensor is communicatively connected to the control cabinet to facilitate the transmission of the cylinder's oil circuit pressure to the control cabinet.
[0008] Preferably, each of the cylinder assemblies includes a cylinder barrel and a cylinder rod. The cylinder barrel has a front end cap and a rear end cap at its two ends. A displacement sensor is installed at the center of the cylinder barrel. The displacement sensor is coaxial with the cylinder rod. The detection end of the displacement sensor is fixedly connected to the center of the tail of the cylinder rod and extends and retracts synchronously with the cylinder rod. The fixed end of the displacement sensor is rigidly connected to the center of the inner side of the rear end cap of the cylinder through a flange. The rear end cap of the cylinder is sealed and fixed to the cylinder barrel.
[0009] Preferably, the hydraulic oil tank has a built-in suction filter and is connected to the hydraulic oil pump inlet via a hose. The hydraulic oil tank's return port is connected to the return oil filter's outlet to facilitate receiving system return oil. The hydraulic oil tank's oil bypass port is connected to the air cooler's inlet and return port to form an oil cooling circuit.
[0010] Preferably, the control cabinet is equipped with a PLC controller and a power supply. The power supply is connected to the PLC controller to facilitate the PLC controller to control the power supply's on / off state. A display is installed on the top of the control cabinet, and the display is connected to the PLC controller to facilitate human-machine interaction.
[0011] This invention also discloses a lifting method for a digitally displayed lifting fixture for urban rail transit, comprising:
[0012] Step S1, Pre-construction preparation: placement of components and equipment debugging;
[0013] Step S2, Parameter Preset: According to the track design drawings, set the design elevation and axis position of the precast slab, and input the hydraulic cylinder lifting speed and adjustment accuracy;
[0014] Step S3, Start Lifting: The PLC controller controls the three-phase asynchronous motor to start, and the three-phase asynchronous motor provides power to lift the hydraulic cylinder assembly;
[0015] Step S4, Lifting Adjustment: The PLC controller adjusts the extension and retraction of the hydraulic cylinder assembly based on the data fed back by the displacement sensor, thereby adjusting the precast slab in the vertical and horizontal directions;
[0016] Step S5, Data Recording and Position Locking: The PLC controller sends a command to lock the oil circuit, keeping the cylinder assembly in its current position, and records the data during the extension and retraction of the cylinder assembly;
[0017] Step S6, Tooling Removal: The PLC controller sends a command to control the hydraulic cylinder assembly to reset and move the mobile platform to the next construction station.
[0018] Preferably, the vertical adjustment involves the PLC controller comparing the current extension / retraction amount of the hydraulic cylinder assembly with the preset target vertical extension / retraction amount in real time to determine whether the current elevation of the precast slab has reached the design value. If yes, the PLC controller sends a command to lock the hydraulic cylinder; if no, the PLC controller sends an upward or retracting command based on the comparison result until the height of the precast slab reaches the design elevation. The horizontal adjustment involves the PLC controller determining the left and right offset direction and amount of the precast slab based on the feedback data from the displacement sensor and the axial deviation of the precast slab, and calculating the differentiated target extension / retraction amount of the hydraulic cylinder assemblies on both sides. The PLC controller then sends a command based on the differentiated extension / retraction amount to achieve differentiated lifting of the hydraulic cylinder assemblies on both sides.
[0019] Compared with the prior art, the present invention has the following advantages:
[0020] 1. The PLC controller of the present invention receives data transmitted by the displacement sensor, the first pressure sensor and the second pressure sensor, and controls the opening degree of the proportional solenoid valve according to the received data. Multiple proportional solenoid valves work together to realize the vertical adjustment of the precast slab. The differentiated valve core opening of the proportional solenoid valves corresponding to the two sets of hydraulic cylinders realizes the horizontal adjustment of the precast slab, thus solving the problem of difficulty in horizontal adjustment of the precast slab.
[0021] 2. The control cabinet of the present invention includes a PLC controller and a display. Through bidirectional communication between the PLC controller and the display, the visualization of the construction situation is improved, while the adjustment efficiency and accuracy are also improved.
[0022] 3. The main oil circuit of this invention is equipped with an overflow valve to stabilize the main oil circuit pressure at 45MPa. The branch oil circuits are equipped with balance valves and pressure sensors to facilitate oil circuit pressure detection and prevent overload and drop load. The air cooler and filter ensure oil cleanliness and temperature stability.
[0023] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention;
[0025] Figure 2 for Figure 1 Enlarged structural diagram at point A;
[0026] Figure 3 for Figure 1 Enlarged structural diagram at point B.
[0027] Explanation of reference numerals in the attached figures:
[0028] 1—Rail; 2—Precast slab; 3—Relief valve; 4—Valve seat; 5—Balancing valve; 6—Second pressure sensor; 7—Proportional solenoid directional valve; 8—Hydraulic oil tank; 9—Air cooler; 10—Return oil filter; 11—Check valve; 12—Three-phase asynchronous motor; 13—Coupling; 14—Hydraulic oil pump; 15—Oil suction filter; 16—Control cabinet; 17—Mobile Platform; 18—Hydraulic oil pipe; 19—Cylinder guard plate; 20—Displacement sensor; 21—Rear end cap of the hydraulic cylinder; 22—Cylinder barrel; 23—Cylinder rod; 24—Cylinder front cover. Detailed Implementation
[0029] like Figures 1 to 3 As shown, this invention discloses a digitally displayed lifting fixture for urban rail transit. The lifting fixture includes a mobile platform 17, with a control cabinet 16 and a hydraulic oil tank 8 at each end along its length. The hydraulic oil tank 8 is connected to a hydraulic oil pump 14, which is coaxially connected to a three-phase asynchronous motor 12. The three-phase asynchronous motor 12 is connected to the control cabinet 16 to facilitate control of the motor. The hydraulic oil pump 14 delivers hydraulic oil to the cylinder assembly via a hydraulic oil line and a hydraulic oil pipe 18 to lift the precast slab 2. There are multiple cylinder assemblies. In the non-working state, the cylinder assemblies are threadedly connected to the mobile platform 17 via an adjustable base at the bottom. In the working state, the cylinder assemblies are placed at the preset lifting point of the precast slab 2. The top of the cylinder assembly is directly opposite the steel lifting pad at the bottom of the precast slab 2 to facilitate vertical and horizontal adjustment of the precast slab 2. The connection between the cylinder assembly and the control cabinet 16 facilitates the transmission of cylinder extension and retraction.
[0030] In this embodiment, there are 6 hydraulic cylinder assemblies, which are divided into two groups and arranged in a rectangular symmetrical pattern to adapt to the structural stress characteristics of the precast rubber spring slab of the urban rail transit. The specific arrangement rule is as follows: with the geometric center of the precast slab 2 as the origin, the two groups of hydraulic cylinder assemblies are arranged on the left and right sides of the precast slab 2, with 3 cylinders on each side. The 3 hydraulic cylinder assemblies on each side are evenly distributed along the length of the precast slab 2, and the 3 hydraulic cylinder assemblies on the same side are kept on the same straight line. The hydraulic cylinder assemblies on the left and right sides are arranged symmetrically to ensure that the precast slab 2 is subjected to uniform force during the lifting process of the hydraulic cylinder assembly, and to avoid deformation or positional displacement of the precast slab 2 due to uneven load. In the non-working state, the bottom of the hydraulic cylinder assembly is threadedly connected to the moving platform 17 through an adjustable base. In the working state, the hydraulic cylinder assembly is placed at the preset lifting point of the precast slab 2, with the top of the cylinder facing the steel lifting pad at the bottom of the precast slab 2. The adjustable base at the bottom of the hydraulic cylinder assembly can be finely adjusted to ensure that the cylinder is in perpendicular contact with the lifting surface of the precast slab 2.
[0031] After the construction personnel input the vertical lifting parameters through the control cabinet 16, the PLC controller inside the control cabinet 16 calculates the target synchronous extension and retraction of the six hydraulic cylinder assemblies based on the design elevation of the precast slab 2, and sends synchronous and equal electrical signal commands to the six proportional solenoid directional valves 7 to ensure that the valve core of each proportional solenoid directional valve 7 opens synchronously to the same degree, so that the hydraulic oil enters the rodless chamber of each hydraulic cylinder assembly at the same flow rate through the balance valve 5 and the hydraulic oil pipe 18, providing equal hydraulic power for the extension of the cylinder rod 23, and ensuring the synchronicity of the lifting and lowering of the six hydraulic cylinder assemblies.
[0032] The displacement sensor 20 built into each hydraulic cylinder assembly transmits the real-time data of the cylinder extension / retraction to the PLC controller. The PLC controller performs real-time comparative analysis of the extension / retraction of the six hydraulic cylinders. If the extension / retraction of a certain hydraulic cylinder deviates from the average value (≤0.1mm), the PLC controller sends a fine-tuning command to the proportional solenoid valve 7 corresponding to that hydraulic cylinder assembly. If the extension / retraction of the hydraulic cylinder is too fast, the valve core opening of the corresponding proportional solenoid valve 7 is reduced to decrease the oil supply flow and slow down the extension speed of the cylinder rod 23. If the extension / retraction of the hydraulic cylinder is too slow, the valve core opening of the corresponding proportional solenoid valve 7 is increased to increase the oil supply flow and accelerate the extension speed of the cylinder rod 23.
[0033] The PLC controller receives real-time expansion and contraction data from six displacement sensors 20. Combined with the precast slab 2 axis position algorithm, it calculates the actual axis offset of the precast slab 2. Pressure sensors 20 collect oil circuit pressure data from the left and right cylinder assemblies and feed it back to the PLC controller to ensure pressure balance. The PLC controller compares the actual axis offset with the design axis (offset = 0), calculates the compensation expansion and contraction of the left and right cylinder assemblies, and determines the secondary target expansion and contraction of each cylinder assembly. The PLC controller sends differentiated fine-tuning commands (different valve core openings on both sides) to the proportional solenoid directional valves 7 on both sides to control the cylinders on both sides with minute and precise expansion and contraction. The axis displacement algorithm is as follows: if the precast slab 2 deviates to the left, the PLC controller sends a command to the three proportional solenoid directional valves 7 on the left to reduce the valve core opening, causing the three valves on the left to... When the hydraulic cylinder retracts, it sends an instruction to increase the valve core opening of the three proportional solenoid directional valves 7 on the right, causing the three hydraulic cylinders on the right to extend, thereby shifting the precast slab 2 to the left. If the precast slab 2 shifts to the right, the PLC controller sends an instruction to decrease the valve core opening of the three proportional solenoid directional valves 7 on the right, causing the three hydraulic cylinders on the right to retract, and sends an instruction to increase the valve core opening of the three proportional solenoid directional valves 7 on the left, causing the three hydraulic cylinders on the left to extend, thereby shifting the precast slab 2 to the right. After the hydraulic cylinder assembly completes the differentiated action, the displacement sensor 20 continues to collect the extension and retraction amount. The PLC controller recalculates the axial offset based on the data transmitted by the displacement sensor 20. If the offset still exceeds the precast slab's design axis, the above cycle is repeated until the axis of the precast slab 2 coincides with the design axis and the offset is ≤0.5mm. At this point, the PLC sends a command to complete the horizontal adjustment.
[0034] The hydraulic circuit includes a check valve 11 and a valve seat 4. The inlet of the check valve 11 is connected to the flange of the hydraulic pump 14, and the outlet of the check valve 11 is connected to the main oil circuit of the valve seat 4. A valve assembly and a proportional solenoid directional valve 7 are installed on the valve seat 4. The inlet of each proportional solenoid directional valve 7 is connected to a portion of the oil circuit within the valve assembly, and the outlet of each proportional solenoid directional valve 7 is connected to the quick-connect fitting of the corresponding cylinder assembly via a hydraulic oil pipe 18. The connector of the proportional solenoid directional valve 7 is connected to the control cabinet 16 for receiving commands.
[0035] A three-phase asynchronous motor 12 is installed on the mobile platform 17. The output shaft of the three-phase asynchronous motor 12 is connected to the input shaft of the hydraulic oil pump 14 through the coupling 13. The three-phase asynchronous motor 12 is connected to the control cabinet 16 to receive start, stop and speed adjustment commands. The hydraulic oil pump 14 is connected to the oil inlet flange of the check valve 11 through a high-pressure hard pipe to output high-pressure hydraulic oil. The oil outlet of the check valve 11 is connected to the main oil circuit of the valve seat 4 to provide equal pressure hydraulic oil to the proportional solenoid directional valve 7.
[0036] In this embodiment, the three-phase asynchronous motor 12 is fixedly installed on the mobile platform 17, adjacent to and coaxially arranged with the hydraulic oil pump 14. The bottom of the three-phase asynchronous motor 12 is bolted to the mobile platform 17 through a shock-absorbing base. The three-phase asynchronous motor 12 provides a power source for the hydraulic oil pump 14, driving the hydraulic oil pump 14 to operate. The speed of the three-phase asynchronous motor 12 is adjusted by the PLC controller to match the power requirements under different working conditions. In use, the PLC controller sends an operation command to the three-phase asynchronous motor 12, and the three-phase asynchronous motor 12 drives the hydraulic oil pump 14 to output high-pressure hydraulic oil. At the same time, the PLC controller sends a synchronous opening command to the six proportional solenoid directional valves 7. The six proportional solenoid directional valves 7 open synchronously to the preset opening degree, and the high-pressure hydraulic oil enters the rodless chamber of the six cylinders synchronously through the valve group and hydraulic oil pipe 18.
[0037] The valve group has a reserved interface for installing an overflow valve 3, a balance valve 5 and a first pressure sensor. The overflow valve 3 stabilizes the main oil circuit pressure at 45MPa to ensure that the oil supply pressure of each cylinder assembly is consistent. The oil circuit of each cylinder assembly is connected in series with a balance valve 5 to facilitate stable lifting. The first pressure sensor is connected to the main oil circuit.
[0038] In this embodiment, the valve group is a combination valve group of 02+6W+Y2. The valve group is integrated and fixed on the valve seat 4. The valve seat 4 is installed in the middle of the moving platform 17 by bolts and is located between the hydraulic oil pump 14 and the cylinder assembly, close to the middle of the main oil circuit, to shorten the hydraulic oil transmission path. The oil inlet of the valve group is connected to the oil outlet of the check valve 11 through a high-pressure hard pipe to access the high-pressure oil of the main oil circuit. The oil return port of the valve group is connected to the oil inlet of the return oil filter 10 through a hard pipe to realize the system return oil. There are 6 proportional solenoid directional valves 7. The 6 proportional solenoid directional valves 7 are the core components of the valve group and are arranged linearly and equidistantly along the valve seat 4. The 6 proportional solenoid directional valves 7 correspond one-to-one with the 6 cylinders. The oil inlet of each proportional solenoid directional valve 7 is connected to the internal oil circuit of the valve group, and the oil outlet is connected to the oil port quick connector of the corresponding cylinder through the hydraulic oil pipe 18. The electrical control terminal of the proportional solenoid directional valve 7 is connected to the PLC controller to receive electrical signal commands.
[0039] The 02+6W+Y2 combined valve group serves as the central control unit for the hydraulic circuit, integrating hydraulic distribution, pressure regulation, and directional control functions. Six proportional solenoid directional valves receive instructions from the PLC controller and adjust the valve core opening according to the received instructions to control the hydraulic oil flow, direction, and on / off state of the corresponding cylinders, enabling independent and coordinated action of the six cylinders. The first pressure sensor is the main pressure sensor, installed at the main hydraulic circuit interface of the valve group. It collects the overall pressure of the main hydraulic circuit in real time and transmits the collected data to the PLC controller, providing pressure data support for PLC closed-loop control.
[0040] A second pressure sensor 6 is installed at the branch oil circuit of the cylinder assembly. The second pressure sensor 6 is communicatively connected to the control cabinet 16 to facilitate the transmission of the oil circuit pressure of the cylinder to the control cabinet 16.
[0041] In this embodiment, there are six second pressure sensors 6. These six second pressure sensors 6 are installed at the branch oil circuit interfaces from the valve group to each cylinder assembly. Each second pressure sensor 6 is integrated on the valve seat 4, close to the oil circuit pressure detection node. The detection end of each second pressure sensor 6 is connected to the branch oil circuit through a threaded interface and is in direct contact with the hydraulic oil to achieve pressure acquisition. The electrical signal end of each second pressure sensor 6 is connected to the PLC controller for data transmission. Each second pressure sensor 6 collects the individual pressure of each cylinder assembly's branch oil circuit in real time and transmits the pressure signal to the PLC controller, which can then detect the oil circuit pressure. When the cylinder rod 23 contacts the precast plate 2, the oil circuit pressure will rise sharply. The second pressure sensor 6 detects the pressure data and transmits the pressure data to the PLC controller. After receiving the pressure signal, the PLC controller can determine that the cylinder has entered the lifting load state and randomly reduce the lifting speed. This, in conjunction with the displacement sensor 20, achieves precise extension and retraction control while preventing cylinder overload.
[0042] The second pressure sensor 6 uses the Danyangfu model sensor.
[0043] Each of the cylinder assemblies includes a cylinder barrel 22 and a cylinder rod 23. The cylinder barrel 22 has a front end cap 24 and a rear end cap 21 at its two ends, respectively. A displacement sensor 20 is installed at the center of the cylinder barrel 22. The displacement sensor 20 is coaxial with the cylinder rod 23. The detection end of the displacement sensor 20 is fixedly connected to the center of the tail of the cylinder rod 23 and extends and retracts synchronously with the cylinder rod 23. The fixed end of the displacement sensor 20 is rigidly connected to the center of the inner side of the rear end cap 21 through a flange. The rear end cap 21 is sealed and fixed to the cylinder barrel 22.
[0044] In this embodiment, the displacement sensor 20 is a magnetostrictive displacement sensor, which realizes non-contact real-time detection of the extension and retraction of the hydraulic cylinder through the magnetostrictive induction principle. The detection process is free of mechanical wear and has high accuracy. The displacement sensor 20 moves synchronously with the hydraulic cylinder rod 23, detects the extension and retraction of the hydraulic cylinder rod 23 in real time, and transmits the detected extension and retraction data to the PLC controller. The PLC controller compares the extension and retraction data with the preset target value and displays the extension and retraction data on the display screen in real time, realizing digital monitoring.
[0045] The detection end of the displacement sensor 20 has no relative displacement with the cylinder rod 23. The cable of the displacement sensor 20 is led out from the dedicated outlet of the cylinder rear cover 21, and after passing through the inside of the cylinder guard plate 19, it is connected to the PLC controller of the control cabinet 16. The cable is waterproof and anti-breakage protected. The built-in installation of the displacement sensor 20 avoids the sensor from being affected by collisions, dust and oil on the construction site. At the same time, the displacement sensor 20 is kept in the same direction as the cylinder extension and retraction, eliminating the deviation of the detection angle of the displacement sensor 20.
[0046] The core components of the displacement sensor 20 include a waveguide (fixed end, stationary with the cylinder), a magnetic ring (detection end, moving synchronously with the cylinder rod), a signal generator, and a signal receiver. The waveguide is axially arranged inside the cylinder, and the magnetic ring is sleeved on the outside of the waveguide and fixed to the tail of the cylinder. The signal generator emits a pulse current into the waveguide, which forms a ring magnetic field around the waveguide. When the ring magnetic field meets the permanent magnetic field of the magnetic ring, a magnetostrictive effect is generated, forming a mechanical strain pulse. The mechanical strain pulse propagates along the waveguide to both ends. The signal receiver receives the pulse and records the time difference between the emitted pulse current and the received mechanical pulse. The PLC controller calculates the distance between the magnetic ring and the signal generator based on the time difference data transmitted by the displacement sensor 20 and the propagation speed of the magnetostrictive wave in the waveguide. This distance is the real-time extension and retraction of the cylinder rod (when the cylinder rod is fully retracted, the extension and retraction is 0, which is used as the detection zero point).
[0047] The hydraulic oil tank 8 has a built-in suction filter 15 and is connected to the oil inlet of the hydraulic oil pump 14 via a hose. The oil return port of the hydraulic oil tank 8 is connected to the oil outlet of the oil return filter 10 to facilitate the receipt of system return oil. The oil bypass port of the hydraulic oil tank 8 is connected to the oil inlet and oil return port of the air cooler 9 to form an oil cooling circuit.
[0048] In this embodiment, the hydraulic oil pump 14 and the three-phase asynchronous motor 12 are coaxially fixed on the mobile platform 17. The hydraulic oil pump 14 converts the mechanical energy transmitted by the three-phase asynchronous motor 12 into hydraulic energy, draws low-pressure hydraulic oil from the hydraulic oil tank 8 and pressurizes it, and outputs high-pressure hydraulic oil that meets the design pressure to the main oil circuit. The hydraulic oil tank 8 and the control cabinet 16 are respectively installed on both sides of the mobile platform 17 to avoid electrical components being contaminated by hydraulic oil. The hydraulic oil tank 8 is a 40-liter volume tank made of 304 stainless steel, which can store 40 liters of hydraulic oil. It has reserved openings for filling, oil level gauge and drain, which is convenient for daily maintenance. The hydraulic oil tank 8 provides a stable oil medium for the hydraulic system, and at the same time realizes the sedimentation, heat dissipation and temporary storage of impurities in the oil. The 304 stainless steel material has corrosion resistance and rust prevention, which is suitable for the humid and dusty site environment of subway construction and avoids oil contamination.
[0049] The control cabinet 16 is equipped with a PLC controller and a power supply. The power supply is connected to the PLC controller to facilitate the PLC controller to control the power supply. A display is installed on the top of the control cabinet 16, and the display is connected to the PLC controller to facilitate human-machine interaction.
[0050] In this embodiment, the external construction power supply provides the main power to the control cabinet 16, and the PLC controller communicates bidirectionally with the display to realize parameter input and data visualization.
[0051] A lifting method for a digitally displayed lifting fixture for urban rail transit includes:
[0052] Step S1, Pre-construction preparation: placement of components and equipment debugging;
[0053] Move the mobile platform 17 to the designated position below the precast slab 2 to be finely adjusted, adjust the level of the mobile platform 17 to ensure that the hydraulic cylinder and the lifting point of the precast slab are accurately aligned, connect the external construction power supply, turn on the main switch of the control cabinet 16 to perform a power-on self-test, confirm that the hydraulic oil tank 8 is in normal condition, manually operate the display to start the three-phase asynchronous motor 12, the three-phase asynchronous motor 12 drives the hydraulic oil pump 14 to run through the coupling 13, the hydraulic oil is sucked in through the suction filter 15, the hydraulic oil pump 14 is filled and then enters the main oil circuit of the valve group through the one-way valve 11, the first pressure sensor collects the initial pressure data and feeds it back to the PLC controller, the PLC controller judges whether the received pressure reaches the design value of 45MPa, the overflow valve 3 is in standby state to ensure that the system has no leakage and the pressure is stable; the PLC controller sends a calibration command to the displacement sensor 20, all hydraulic cylinder rods 23 are reset to the initial position, the displacement sensor 20 records the zero point data, the first pressure sensor and the second pressure sensor are zeroed, and after the debugging is completed, it enters the standby state.
[0054] Step S2, Parameter Preset: According to the track design drawings, set the design elevation and axis position of the precast slab, and input the hydraulic cylinder lifting speed and adjustment accuracy;
[0055] According to the track design drawings, the design elevation (vertical direction) and design axis position (horizontal direction) of the precast slab are input on the display interface of control cabinet 16. At the same time, construction parameters such as lifting speed and adjustment accuracy are input. The PLC controller allocates the target extension and retraction amount of each hydraulic cylinder according to the size of the precast slab and the arrangement of the 6 hydraulic cylinders. Vertical adjustment is the synchronous extension and retraction amount of the 6 hydraulic cylinders, and horizontal adjustment is the differentiated extension and retraction amount of the hydraulic cylinders on both sides. The PLC controller stores each parameter as the adjustment reference.
[0056] Step S3, Start Lifting: The PLC controller controls the three-phase asynchronous motor 12 to start, and the three-phase asynchronous motor 12 provides power to make the hydraulic cylinder lift.
[0057] The PLC controller sends an operation command to the three-phase asynchronous motor 12, which drives the hydraulic oil pump 14 to output high-pressure hydraulic oil. Simultaneously, the PLC controller sends a synchronous opening command to the six proportional solenoid directional valves 7. The valve cores of the proportional solenoid directional valves 7 synchronously open to the preset opening degree. The high-pressure hydraulic oil enters the rodless chamber of the six cylinders synchronously through the valve group and hydraulic oil pipe 18. The hydraulic oil pushes the cylinder rod 23 upwards, and the cylinder guard plate 19 extends and retracts synchronously with the cylinder rod 23 for protection. The displacement sensor 20 collects the extension and retraction of each cylinder rod 23 in real time. The first pressure sensor and the second... Pressure sensor 6 collects the lifting pressure data of the hydraulic cylinder, and all data is transmitted to the PLC controller in real time. When the top of the hydraulic cylinder rod 23 contacts the bottom of the precast slab, the second pressure sensor detects a sudden increase in oil pressure and feeds it back to the PLC controller. The PLC controller sends a command to reduce the valve core opening of the proportional solenoid valve 7 and reduce the lifting speed until the precast slab is steadily lifted 5-10mm (away from the initial bottom support). The PLC controller then sends a command to stop the operation of the proportional solenoid valve 7, the hydraulic cylinder maintains its current position, and the balance valve 5 locks the hydraulic cylinder oil circuit to prevent the precast slab from falling.
[0058] Step S4, Lifting Adjustment: The PLC controller adjusts the extension and retraction of the hydraulic cylinder based on the data fed back by the displacement sensor 20, thereby adjusting the precast slab in the vertical and horizontal directions;
[0059] The PLC controller enables precise coordination of six hydraulic cylinders to complete vertical and horizontal adjustments. Vertical and horizontal adjustments can be performed continuously without stopping the machine, with an adjustment accuracy of ≤0.5mm. The PLC controller compares the current extension and retraction of the six hydraulic cylinders collected by the displacement sensor 20 with the preset target vertical extension and retraction in real time to determine whether the current elevation of the precast slab has reached the design value.
[0060] If the elevation of the precast slab does not reach the design value, the PLC controller sends a synchronous and equal opening command to the six proportional solenoid directional valves 7. The high-pressure hydraulic oil continues to enter the rodless chamber of the cylinder synchronously, and the six cylinders extend upward synchronously. The displacement sensor 20 provides real-time feedback on the extension and retraction amount, so that the six cylinders rise steadily.
[0061] If the elevation of the precast slab reaches the design value, the PLC controller sends a command to close the valve core of the proportional solenoid directional valve 7, the balance valve 5 locks the oil circuit again, the oil cylinder maintains the lifting position, and the precast slab completes the precise vertical adjustment.
[0062] If the elevation of the precast slab exceeds the design value, the PLC controller sends a command to the proportional solenoid valve 7 to open in the reverse direction, and the cylinder rod 23 of the corresponding cylinder retracts slightly until the elevation of the precast slab reaches the design value.
[0063] When adjusting the precast slab horizontally, six hydraulic cylinders extend and retract differently. The PLC controller, based on the data fed back by displacement sensor 20 and the axial deviation of the precast slab, determines the left and right offset direction and amount of the precast slab, and calculates the differentiated target extension and retraction amount of the hydraulic cylinders on both sides. If the precast slab shifts to the left, the left hydraulic cylinder retracts slightly and the right hydraulic cylinder extends slightly; if the precast slab shifts to the right, the right hydraulic cylinder retracts slightly and the left hydraulic cylinder extends slightly.
[0064] The PLC controller sends differentiated opening commands to the proportional solenoid valves 7 on the corresponding sides of the hydraulic cylinders on the left and right sides of the precast slab. The PLC controller controls the valve core opening degree and opening time of the proportional solenoid valves 7 on both sides, so as to realize the micro-precision extension and retraction of the hydraulic cylinders on one or both sides of the precast slab. The hydraulic oil enters the corresponding hydraulic cylinder through the balance valve 5, pushes the hydraulic cylinder rod 23 to perform differentiated actions, and drives the bottom of the precast slab to move left and right, thereby realizing the horizontal adjustment of the precast slab.
[0065] Displacement sensor 20 collects the extension and retraction of each cylinder in real time, second pressure sensor 6 monitors the pressure balance of the oil circuits on both sides, and PLC controller compares the real-time data with the preset horizontal target parameters. If there is a deviation, it will continuously issue correction commands until the axis of the precast slab coincides with the design axis, and then the horizontal adjustment of the precast slab is completed.
[0066] During the adjustment process, if the oil circuit pressure exceeds the preset value, the second pressure sensor 6 will feed back the overpressure signal to the PLC controller. The PLC controller will send a command to the relief valve 3 to open the relief valve 3 to release pressure. At the same time, the PLC controller will send a command to the proportional solenoid directional valve 7 to reduce the opening of the proportional solenoid directional valve 7 to ensure stable oil circuit pressure. If the hydraulic oil temperature rises, the PLC controller will send a command to start the air cooler 9 to cool the hydraulic oil.
[0067] Step S5, Data Recording and Position Locking: The PLC controller sends a command to lock the oil circuit, keeping the oil cylinder in its current position, and records the data during the extension and retraction of the oil cylinder;
[0068] After the precast slab meets the design requirements in both the vertical and horizontal directions, the PLC controller sends a command to close the six proportional solenoid directional valves 7 and the balance valve 5 to lock the hydraulic cylinder circuit. The hydraulic cylinder maintains its final adjusted position, completing the fine-tuning and positioning of the precast slab. The PLC controller saves the construction data and displays it on the monitor. The construction data includes the hydraulic cylinder extension and retraction, hydraulic circuit pressure, adjustment time, and the final coordinates of the precast slab. Construction personnel can view and export the data through the monitor as a reference for construction acceptance and subsequent track laying. After the precast slab is positioned in both the horizontal and vertical directions, the lifting fixture maintains its current position until the precast slab is fixed. At the same time, the displacement sensor 20 continuously monitors the displacement of the precast slab. If the position of the precast slab shifts, the PLC controller sends a correction command based on the data sent by the displacement sensor 20 to adjust the position of the precast slab.
[0069] Step S6, Tooling Removal: The PLC controller sends a command to control the hydraulic cylinder to reset and move the mobile platform 17 to the next construction station.
[0070] After the precast slab is fixed on site, a lifting tool removal command is issued via the display. This removal command is transmitted to the PLC controller, which sends a reverse opening command to the six proportional solenoid directional valves 7. The hydraulic oil in the rodless chamber of the cylinder flows back to the hydraulic oil tank 8 after being filtered by the proportional solenoid directional valves 7 and the return oil filter 10. If the oil temperature is high, the PLC controller controls the air cooler 9 to start. The hydraulic oil is cooled by the air cooler 9 before flowing back to the hydraulic oil tank 8. The cylinder rod 23 retracts smoothly to its initial position under the action of the hydraulic oil return and the supporting force of the precast slab. After the displacement sensor 20 detects the cylinder reset, it sends a feedback signal to the PLC controller. The PLC controller sends a stop command to the three-phase asynchronous motor 12. After receiving the stop command, the three-phase asynchronous motor 12 stops running, the hydraulic oil pump 14 stops supplying oil, and the oil pressure returns to normal pressure. The main switch of the control cabinet 16 is turned off, the external power supply is disconnected, and the mobile platform 17 is pushed to the next precast slab station to be finely adjusted. The above steps are repeated.
[0071] The vertical adjustment is achieved by the PLC controller comparing the current extension and retraction of the hydraulic cylinder with the preset target vertical extension and retraction in real time to determine whether the current elevation of the precast slab has reached the design value.
[0072] If so, the PLC controller sends a command to lock the hydraulic cylinder;
[0073] If not, the PLC controller sends an upward or downward command based on the comparison result until the height of the precast slab reaches the design elevation.
[0074] The horizontal adjustment is achieved by the PLC controller determining the left and right offset direction and amount of the precast slab based on the feedback data from the displacement sensor 20 and the axial deviation of the precast slab, and calculating the differentiated target extension and retraction amount of the two hydraulic cylinders. The PLC controller then sends a command to the two hydraulic cylinders to achieve differentiated lifting based on the differentiated extension and retraction amount.
[0075] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.
Claims
1. A digitally displayed lifting fixture for urban rail transit, characterized in that: The lifting fixture includes a mobile platform (17), with a control cabinet (16) and a hydraulic oil tank (8) at both ends along its length. The hydraulic oil tank (8) is connected to a hydraulic oil pump (14), which is coaxially connected to a three-phase asynchronous motor (12). The three-phase asynchronous motor (12) is connected to the control cabinet (16) to facilitate the control of the motor. The hydraulic oil pump (14) is connected to a hydraulic oil pipe (18) via a hydraulic circuit. Hydraulic oil is delivered to the cylinder assembly to lift the precast slab (2). There are multiple cylinder assemblies. When not in operation, the cylinder assembly is threadedly connected to the moving platform (17) through the adjustable base at the bottom. When in operation, the cylinder assembly is placed at the preset lifting point of the precast slab (2). The top of the cylinder assembly is directly opposite the steel lifting pad at the bottom of the precast slab (2) to facilitate vertical and horizontal adjustment of the precast slab (2). The cylinder assembly is connected to the control cabinet (16) to facilitate the transmission of cylinder extension and retraction.
2. The digital display jacking fixture for urban rail transit according to claim 1, characterized in that: The hydraulic circuit includes a check valve (11) and a valve seat (4). The inlet of the check valve (11) is connected to the flange of the hydraulic pump (14). The outlet of the check valve (11) is connected to the main oil circuit of the valve seat (4). A valve group and a proportional solenoid directional valve (7) are installed on the valve seat (4). The inlet of each proportional solenoid directional valve (7) is connected to a part of the oil circuit inside the valve group. The outlet of each proportional solenoid directional valve (7) is connected to the quick connector of the corresponding cylinder assembly through a hydraulic oil pipe (18). The connector of the proportional solenoid directional valve (7) is connected to the control cabinet (16) for easy receiving of commands.
3. A digitally displayed jacking fixture for urban rail transit according to claim 2, characterized in that: The valve group has a reserved interface for installing an overflow valve (3), a balance valve (5) and a first pressure sensor. The overflow valve (3) stabilizes the main oil circuit pressure at 45MPa to ensure that the oil supply pressure of each cylinder assembly is consistent. The oil circuit of each cylinder assembly is connected in series with a balance valve (5) to facilitate stable lifting. The first pressure sensor is connected to the main oil circuit.
4. A digitally displayed jacking fixture for urban rail transit according to claim 1, characterized in that: A second pressure sensor (6) is installed at the branch oil circuit of the cylinder assembly. The second pressure sensor (6) is communicatively connected to the control cabinet (16) to facilitate the transmission of the oil circuit pressure of the cylinder to the control cabinet (16).
5. A digitally displayed jacking fixture for urban rail transit according to claim 1, characterized in that: Each of the cylinder assemblies includes a cylinder barrel (22) and a cylinder rod (23). The cylinder barrel (22) has a front end cap (24) and a rear end cap (21) at its two ends. A displacement sensor (20) is installed at the center of the cylinder barrel (22). The displacement sensor (20) is coaxial with the cylinder rod (23). The detection end of the displacement sensor (20) is fixedly connected to the center of the tail of the cylinder rod (23) and extends and retracts synchronously with the cylinder rod (23). The fixed end of the displacement sensor (20) is rigidly connected to the center of the inner side of the rear end cap (21) through a flange. The rear end cap (21) is sealed and fixed to the cylinder barrel (22).
6. A digitally displayed jacking fixture for urban rail transit according to claim 1, characterized in that: The hydraulic oil tank (8) has a built-in suction filter (15) and is connected to the oil inlet of the hydraulic oil pump (14) through a hose. The oil return port of the hydraulic oil tank (8) is connected to the oil outlet of the oil return filter (10) to facilitate the receiving of system return oil. The oil bypass port of the hydraulic oil tank (8) is connected to the oil inlet and oil return port of the air cooler (9) to form an oil cooling circuit.
7. A digitally displayed jacking fixture for urban rail transit according to claim 1, characterized in that: The control cabinet (16) is equipped with a PLC controller and a power supply. The power supply is connected to the PLC controller to facilitate the PLC controller to control the power supply. A display is installed on the top of the control cabinet (16). The display is connected to the PLC controller to facilitate human-machine interaction.
8. The lifting method of the digital jacking fixture for urban rail transit according to any one of claims 1-7, characterized in that, include: Step S1, Pre-construction preparation: placement of components and equipment debugging; Step S2, parameter preset: According to the track design drawings, set the design elevation and axis position of the precast slab (2), and input the cylinder lifting speed and adjustment accuracy; Step S3, Start Lifting: The PLC controller controls the three-phase asynchronous motor (12) to start, and the three-phase asynchronous motor (12) provides power to lift the hydraulic cylinder assembly; Step S4, Lifting Adjustment: The PLC controller adjusts the extension and retraction of the hydraulic cylinder assembly based on the data fed back by the displacement sensor (20) to realize the adjustment of the precast slab (2) in the vertical and horizontal directions; Step S5, Data Recording and Position Locking: The PLC controller sends a command to lock the oil circuit, keeping the cylinder assembly in its current position, and records the data during the extension and retraction of the cylinder assembly; Step S6, Tooling Removal: The PLC controller sends an instruction to control the hydraulic cylinder assembly to reset and move the mobile platform (17) to the next construction station.
9. The lifting method of the digital display lifting fixture for urban rail transit according to claim 8, characterized in that, The vertical adjustment is achieved by the PLC controller comparing the current extension and retraction of the hydraulic cylinder assembly with the preset target vertical extension and retraction in real time to determine whether the current elevation of the precast slab has reached the design value. If so, the PLC controller sends a command to lock the hydraulic cylinder; If not, the PLC controller sends an upward or downward command based on the comparison result until the height of the precast plate (2) reaches the design elevation; The horizontal adjustment is achieved by the PLC controller determining the left and right offset direction and offset amount of the precast plate (2) based on the feedback data of the displacement sensor (20) and the axis deviation of the precast plate (2), and calculating the differentiated target extension and retraction amount of the cylinder assemblies on both sides. The PLC controller sends a command based on the differentiated extension and retraction amount to make the cylinder assemblies on both sides achieve differentiated lifting.