TBM hob rock breaking experiment platform based on numerical control machine tool

Abstract

The utility model discloses a TBM hob rock breaking experiment platform based on a numerical control machine tool, which comprises a workbench fixed on the numerical control machine tool, the workbench is provided with a confining pressure loading unit, and the confining pressure loading unit is used for fixing a rock sample and applying confining pressure for simulating stratum stress to the rock sample; the confining pressure loading unit right faces the hob system, the hob system is provided with a bearing table, a power device is arranged on the bearing table, an output shaft of the power device is connected with a speed reducer, an output shaft of the speed reducer is connected with a main shaft through a coupler, the main shaft is connected with a hob position adjusting unit, and the hob position adjusting unit is connected with two hob modules. The two hobbing cutter modules are respectively provided with a hobbing cutter directly facing the confining pressure loading unit; the hob position adjusting unit is used for adjusting the distance between the two hobs. According to the utility model, high-precision simulation experiments can be carried out, experimental errors are reduced, and the device is suitable for TBM hob experiments and is also suitable for scale experiments and full-size experiments.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of TBM disc cutter rock breaking simulation experiment. BACKGROUND

[0002] With the rapid development of transportation infrastructure construction, tunnel engineering is increasingly extending to deep complex strata. Tunnel boring machine (TBM) has become the core equipment for long tunnel construction due to its efficient, continuous and safe operation advantages. However, in the process of tunneling in hard rock strata, the disc cutter bears high stress impact and severe wear, resulting in frequent replacement of cutters and soaring construction costs. Therefore, in-depth study of disc cutter rock breaking mechanism and optimization of cutter design and arrangement form have become the key to improving TBM tunneling efficiency.

[0003] Currently, the research on disc cutter rock breaking mechanism mainly relies on two types of test platforms:

[0004] Full-size disc cutter test bench and scaled disc cutter test bench.

[0005] Full-size test bench directly uses actual cutter size, which can better restore the interaction between TBM cutter head and rock mass, but it has significant defects such as large equipment, long experimental period and high cost, which is difficult to meet the needs of multi-condition and high-frequency experiments.

[0006] The scaled test bench reduces the size of the cutter by equal proportion, which reduces the experimental cost and period, but has the following limitations in simulation degree:

[0007] Insufficient mechanical similarity: traditional scaled bench ignores complex physical fields such as cutting heat and dynamic load fluctuation, making it difficult to truly reflect the stress distribution and temperature field changes during disc cutter rock breaking;

[0008] Geometric matching deviation: the cutter arrangement form is fixed, which cannot flexibly simulate the influence of different cutter head layouts on rock breaking efficiency;

[0009] Parameter control is rough: the rock sample feeding and cutter movement precision are low, resulting in systematic deviation between experimental data and actual working conditions.

[0010] To solve the above contradictions, an innovative test platform that can efficiently carry out experiments and accurately simulate real working conditions is urgently needed. Therefore, the applicant has two design ideas:

[0011] 1. High-precision simulation, high cost, both scaled and full-size experiments can be carried out; the overall effect is better than the second design idea.

[0012] 2. Improve simulation accuracy, lower cost, can carry out scaled experiments, the effect is significantly improved compared with the past, and the experimental efficiency is higher.

[0013] After the above two design ideas are implemented, the device of the second idea can be used for low-cost and rapid scaledown pre-research work, and the device of the first idea can be used for full-size experimental verification and accurate optimization, so that resource waste is reduced and research achievement transformation efficiency is improved.

[0014] The utility model implements the above first design idea. Utility model content

[0015] The utility model discloses a TBM cutter rock breaking experimental platform based on a numerical control machine tool, which utilizes the precision and large space of the numerical control machine tool to provide equipment basis for realizing high-precision simulation experiments, and can be used for scaledown experiments and full-size experiments.

[0016] To achieve the above object, the utility model discloses a TBM cutter rock breaking experimental platform based on a numerical control machine tool includes the workstation fixed on the numerical control machine tool, it is characterized by: the workstation is equipped with the confining pressure loading unit, and the confining pressure loading unit is used for fixing the rock sample and applying the confining pressure of the simulated formation stress to the rock sample.

[0017] The confining pressure loading unit is opposite to the cutter system, the cutter system has a bearing table, the bearing table is equipped with a power device, the output shaft of the power device is connected with a speed reducer, the output shaft of the speed reducer is connected with a main shaft through a shaft coupling, the main shaft is connected with a cutter position adjusting unit, the cutter position adjusting unit is connected with two cutter modules, and the two cutter modules are opposite to the confining pressure loading unit respectively; the cutter position adjusting unit is used for adjusting the distance between the two cutters.

[0018] The confining pressure loading unit includes a portal frame, three hydraulic cylinders and three confining pressure applying plates.

[0019] The portal frame is fixed on the workstation, and the hydraulic cylinders correspond to the three confining pressure applying plates one by one.

[0020] The three hydraulic cylinders are vertically installed on the top beam and the inner sides of the left and right legs of the portal frame respectively, the piston rods of the hydraulic cylinders are hinged to the confining pressure applying plates through universal joints, and the inner surfaces of the confining pressure applying plates are all provided with flexible material layers.

[0021] The confining pressure applying plates are used for sticking to the rock sample surface and uniformly transmitting the confining pressure when working.

[0022] An L-shaped baffle is installed on the workstation behind the confining pressure loading unit, the vertical plate of the L-shaped baffle faces forward and is used for positioning the rear end position of the rock sample, and the horizontal plate of the L-shaped baffle is fixedly connected with the workstation through bolts; and a diagonal brace is fixedly connected between the vertical plate and the horizontal plate of the L-shaped baffle.

[0023] The brake unit includes a brake disc and a caliper.

[0024] The brake disc is fixed to the end of the main shaft and rotates synchronously with the main shaft;

[0025] The caliper is fixed on the bearing table through the support, and the brake pad of the caliper is parallel to the contact surface of the brake disc;

[0026] The caliper is driven by hydraulic or pneumatic drive to achieve the locking or release of the brake disc.

[0027] The direction of the main shaft towards the confining pressure loading unit is the rear direction,

[0028] The position adjusting unit of the hob comprises an open-ended box body, and the front side wall of the box body is fixedly connected with the rear end of the main shaft through a connecting disc and is driven to rotate by the main shaft;

[0029] A lead screw is arranged in the box body, and the lead screw extends in the left-right direction and is rotatably connected with the left and right side walls of the box body through bearings at both ends thereof;

[0030] A worm wheel is fixedly installed at the middle part of the lead screw, and a worm is engagedly connected with the worm wheel, and the upper and lower ends of the worm are rotatably matched with the upper wall and the bottom wall of the box body, respectively; the upper end of the worm extends out of the top wall of the box body and the extended part serves as a hand holding part;

[0031] A lead screw slider is symmetrically and threadedly connected with the lead screw on the left and right sides of the worm wheel, and the rotation directions of the threads on the lead screws on the left and right sides of the worm are opposite; the lead screw sliders correspond to the hob modules one by one and are used for driving the hob modules;

[0032] When the lead screw rotates, the two lead screw sliders are driven to synchronously approach or synchronously move away from the worm wheel in the axial direction.

[0033] The rear top wall of the box body is connected with an upper sliding rail at the rear end, the upper sliding rail is slidably embedded with the upper sliding groove through a dovetail groove structure, the rear bottom wall of the box body is connected with a lower sliding rail at the rear end, and the lower sliding rail is slidably embedded with the lower sliding groove through a dovetail groove structure;

[0034] The hob module comprises a tool holder front plate, the upper end of the tool holder front plate is fixedly connected with the rear wall surface of the upper sliding groove through screws, and the lower end of the tool holder front plate is fixedly connected with the rear wall surface of the lower sliding groove through screws; the middle part of the tool holder front plate is fixedly connected with the lead screw slider in front; the tool holder front plate is fixedly connected with a tool holder at the rear, a hob is installed in the tool holder, and the hob protrudes out of the tool holder at the rear.

[0035] A vertical position adjusting structure of the hydraulic oil cylinder is arranged in the confining pressure loading unit, and a plurality of rows of positioning holes are arranged on the left and right legs of the portal frame, and the positioning holes are uniformly and vertically spaced apart;

[0036] The hydraulic oil cylinder is fixed with the positioning hole through bolts, and is locked after the height is adjusted.

[0037] The three-way force gauge is connected with the wireless communication module, the box body or the tool holder is connected with the storage battery, the three-way force gauge and the wireless communication module are connected with the storage battery respectively, the three-way force gauge is used for monitoring three-way stress data of the hob, and the wireless communication module is used for communication of a control system of the numerical control machine tool.

[0038] The support is fixedly connected with a positioning ring in the rear, and an annular track groove is arranged in the circumferential inner surface of the positioning ring;

[0039] Rollers are connected to the front surface of the box body, and the rollers are embedded in the track groove and rollingly matched with the track groove.

[0040] The coupling is provided with a torque and rotating speed sensor, and the circuit of the torque and rotating speed sensor is connected with the control system of the numerical control machine tool.

[0041] The utility model has the advantages that:

[0042] The utility model has the advantages that:

[0043] 1. High precision and expandability are combined:

[0044] The numerical control machine tool fixing workbench fully utilizes the micron-level movement control capability of the X / Y axis of the numerical control machine tool, accurately simulates the dynamic rock breaking behavior (such as axial advancing speed and cutter track precision) during TBM tunneling, and greatly reduces experimental data error.

[0045] The confining pressure loading unit is directly integrated on the workbench connected with the numerical control machine tool, is suitable for different sizes of rock samples (full size or scaled down), breaks through the limitation that the traditional scaled down platform cannot be compatible with full size experiments, and expands experimental scenarios.

[0046] 2. Real working condition restoration ability is improved:

[0047] The confining pressure loading unit simulates stratum stress: through hydraulic or mechanical pressure, the three-way stress state of the actual roadway surrounding rock is restored, the problem that the traditional platform ignores the confining pressure and causes insufficient mechanical similarity is solved, and the stress distribution matching degree is greatly improved compared with the previous experimental device.

[0048] Double hob module synergistic effect: two hobs are symmetrically arranged, the stress superposition effect of the multi-cutter synergistic rock breaking of the TBM cutterhead is simulated, and the rock mass crushing mechanism during actual tunneling is closer.

[0049] 3. Experimental flexibility and efficiency optimization:

[0050] Cutter position adjustment unit (worm + screw block): manually adjust the cutter spacing and self-locking, adapt to different cutter layout (such as single, double, multiple staggered arrangement), no longer need to replace the cutter module when switching working conditions, and no need to replace the positioning structure between the cutters, so the efficiency of working condition switching is greatly improved.

[0051] Through linkage control of the reducer and the power device, speed-torque dynamic matching can be realized, covering the full formation simulation demand from hard rock to soft rock, and improving the experimental parameter adjustment efficiency.

[0052] 4. Enhanced structural rigidity and stability:

[0053] Numerical control machine tool rigid base + bearing table integrated design: offsetting rock breaking reaction force and vibration, cutter displacement deviation is less than 0.2mm during the experiment, data reliability is significantly improved.

[0054] Modular cutter system: cutter module can be quickly replaced (full size / scale down), avoiding the time-consuming problem of disassembly and reorganization of traditional test benches, and greatly reducing maintenance costs.

[0055] The confining pressure loading unit has the following technical advantages: true surrounding rock stress simulation: through synchronous pressure application by three-way hydraulic cylinders, the three-way stress state of the surrounding rock of the roadway is accurately simulated, and the stress distribution error is ≤5%;

[0056] Pressure uniformity: universal joint and confining pressure application plate cooperate, flexible material layer adapts to the rough surface of the rock sample, avoiding local stress concentration;

[0057] Structural rigidity: gantry and numerical control machine tool workbench rigid connection, offsetting rock breaking reaction force, displacement deviation is less than 0.3mm during the experiment. Inclined struts can enhance the structural strength.

[0058] The brake unit has the following advantages:

[0059] Mode switching flexibility: when braking, the main shaft stops rotating and the cutter is fixed, and linear rock breaking is simulated by numerical control machine tool Y-axis feeding; when released, the main shaft drives the cutter to rotate, and the switching time is <10 seconds;

[0060] Braking stability: caliper symmetrically clamps the brake disc, there is no unbalanced vibration during braking, and the speed fluctuation is <2%;

[0061] Compatibility: brake disc and main shaft integrated design, no interference with the normal operation of the reducer and coupling.

[0062] The position adjusting unit of the rolling cutter is adopted, and the rolling cutter spacing is very convenient to adjust: the staff manually rotates the pinch part, and then two screw rod sliders are driven to approach or move away from each other, the spacing is very convenient to adjust, no component needs to be replaced, and the working condition switching time is shortened by more than 60%. The worm gear transmission ratio is greater than or equal to 20:1, the manual adjustment rolling cutter spacing accuracy is ±0.1mm; the worm gear reverse self-locking characteristic ensures that the rolling cutter spacing is fixed during the experiment, and the vibration displacement is less than 0.05mm.

[0063] The rolling cutter module is convenient and fast to replace, and only needs to dismount or tighten the screws between the cutter holder front plate and the rear wall surface of the sliding groove to dismount or replace the rolling cutter module.

[0064] The upper slide rail and the lower slide rail constrain the rolling cutter module and the screw rod slider from rotating, and when the screw rod rotates, the two screw rod sliders and the two rolling cutter modules will naturally approach or move away from each other.

[0065] The vertical height of the hydraulic oil cylinder can be conveniently adjusted by connecting the positioning holes at different heights, so as to adapt to the confining pressure loading needs of rock samples of different sizes.

[0066] The three-way force gauge can synchronously measure the radial force (Fx), the tangential force (Fy) and the axial force (Fz) when the rolling cutter breaks rocks, and transmit the data to the control system of the numerical control machine tool in real time through the wireless communication module, so as to provide a basis for dynamically adjusting the feeding speed or the confining pressure parameters.

[0067] The positioning ring limits the rotation track of the box body, improves the stability of the rolling cutter rotation and the accuracy of the rotation track. The torque speed sensor transmits torque and speed signals to the control system of the numerical control machine tool in real time, so as to facilitate monitoring the experiment state and analyzing the rock breaking energy consumption. BRIEF DESCRIPTION OF DRAWINGS

[0068] Figure 1 It is a structural schematic diagram of the utility model.

[0069] Figure 2 It is a three-dimensional structural schematic diagram of the utility model.

[0070] Figure 3 It is a three-dimensional structural schematic diagram of the utility model from another angle.

[0071] Figure 4 It is Figure 1 An enlarged view of A in FIG. 1.

[0072] Figure 5 It is a structural schematic diagram between the brake disc and the rolling cutter.

[0073] Figure 6 It is Figure 5 A left view of FIG. 1.

[0074] Figure 7 It isFigure 5 CC section view.

[0075] Figure 8 yes Figure 5 DD sectional view.

[0076] Figure 9 yes Figure 5 A schematic diagram of the three-dimensional structure. Detailed Implementation

[0077] In this invention, the direction of the main shaft 6 toward the confining pressure loading unit is called the rearward direction, and the opposite direction is called the forward direction.

[0078] like Figures 1 to 9 As shown, the TBM roller rock breaking experimental platform based on CNC machine tool includes a worktable 1 fixed on the CNC machine tool. The worktable 1 is equipped with a confining pressure loading unit, which is used to fix the rock sample and apply confining pressure simulating formation stress to the rock sample.

[0079] The confining pressure loading unit faces the roller cutter system. The roller cutter system has a support platform 2, on which a power unit 3 (such as a motor) is installed. The output shaft of the power unit 3 is connected to a reducer (box) 4. The output shaft of the reducer 4 is connected to a main shaft 6 through a coupling 5. The main shaft 6 is connected to a roller cutter position adjustment unit. The roller cutter position adjustment unit is connected to two roller cutter modules. Each of the two roller cutter modules has a roller cutter facing the confining pressure loading unit. The roller cutter position adjustment unit is used to adjust the distance between the two roller cutters.

[0080] This utility model has the following advantages:

[0081] 1. Combination of high precision and scalability:

[0082] By using the fixed worktable 1 of the CNC machine tool, the micron-level movement control capability of the X / Y axis of the CNC machine tool is fully utilized to accurately simulate the dynamic rock-breaking behavior (such as axial advance speed and tool trajectory accuracy) during TBM tunneling, and significantly reduce experimental data errors.

[0083] The confining pressure loading unit is directly integrated on the worktable 1 connected to the CNC machine tool, which is compatible with rock samples of different sizes (full size or scaled-down), breaking through the limitation that traditional scaled-down platforms cannot be compatible with full-size experiments and expanding the experimental scenarios.

[0084] 2. Improved ability to reproduce realistic working conditions:

[0085] The confining pressure loading unit simulates formation stress: by applying hydraulic or mechanical pressure, it restores the triaxial stress state of the actual roadway surrounding rock, solving the problem of insufficient mechanical similarity caused by the neglect of confining pressure in traditional platforms. The stress distribution matching degree is significantly improved compared with previous experimental devices.

[0086] Double-roller module synergy: two symmetrical rollers are arranged to simulate the stress superposition effect of multiple cutters on the TBM cutterhead, which is more in line with the actual rock breaking mechanism during tunneling.

[0087] 3. Experimental flexibility and efficiency optimization:

[0088] Roller position adjustment unit (worm and screw + screw block): manually adjust the roller spacing and self-locking, suitable for different cutterhead layouts (such as single cutter, double cutter, and multiple cutter staggered arrangement), no need to replace the roller module and the positioning structure between the rollers when switching working conditions, thus greatly improving the efficiency of working condition switching.

[0089] Through linkage control of the reducer 4 and the power device 3, the speed-torque dynamic matching can be realized, covering the full formation simulation requirements from hard rock to soft rock, and improving the experimental parameter adjustment efficiency.

[0090] 4. Enhanced structural rigidity and stability:

[0091] Numerical control machine tool rigid base + bearing table 2 integrated design: offsetting rock breaking reaction force and vibration, roller displacement deviation is less than 0.2mm during the experiment process, data reliability is significantly improved.

[0092] Modular roller system: roller module can be quickly replaced (full size / scale down), avoiding the time-consuming problem of traditional test bench disassembly and reorganization, and greatly reducing maintenance cost.

[0093] The confining pressure loading unit comprises a portal frame 7, three hydraulic cylinders 8 and three confining pressure applying plates 9;

[0094] The portal frame 7 is fixed on the workbench 1, and the hydraulic cylinders 8 correspond to the three confining pressure applying plates 9 one by one;

[0095] The three hydraulic cylinders 8 are respectively vertically installed on the top beam and the inner sides of the left and right legs of the portal frame 7, and the piston rods of the hydraulic cylinders 8 are hinged to the confining pressure applying plates 9 through universal joints 10; the inner surfaces of each confining pressure applying plate 9 are provided with a flexible material layer (such as a rubber layer); under the inspiration of the present application, those skilled in the art have the ability to choose appropriate materials to make the flexible material layer, which is not shown in the figure.

[0096] The confining pressure applying plate 9 is in contact with the rock sample surface during work and is used for uniformly transmitting confining pressure;

[0097] An L-shaped baffle 11 is installed on the workbench 1 behind the confining pressure loading unit, the vertical plate of the L-shaped baffle 11 faces forward and is used for positioning the rear end position of the rock sample, and the horizontal plate of the L-shaped baffle 11 is fixedly connected with the workbench 1 through bolts; the vertical plate and the horizontal plate of the L-shaped baffle 11 are fixedly connected with the inclined brace 12.

[0098] The confining pressure loading unit has the following technical advantages:

[0099] Real surrounding rock stress simulation: through the synchronous pressure of three-way hydraulic cylinder 8, the three-way stress state of the surrounding rock of the roadway is accurately simulated, and the stress distribution error is less than or equal to 5%;

[0100] Pressure uniformity: universal joint 10 cooperates with confining pressure application plate 9, flexible material layer self-adapts to the rough surface of the rock sample, and local stress concentration is avoided;

[0101] Structural rigidity: gantry 7 is rigidly connected with the numerical control machine tool workbench 1, counteracts the rock breaking reaction force, and the displacement deviation is less than 0.3 mm during the experiment. The inclined brace 12 can enhance the structural strength.

[0102] The brake unit comprises a brake disc 13 and a caliper 14;

[0103] The brake disc 13 is fixed to the end part of the main shaft 6 and rotates synchronously with the main shaft 6;

[0104] The caliper 14 is fixed on the bearing table 2 through a support 15, and the brake pad of the caliper 14 is parallel to the contact surface of the brake disc 13;

[0105] The caliper 14 is driven by hydraulic pressure or pneumatic pressure to realize the locking or releasing of the brake disc 13.

[0106] The brake unit has the following advantages:

[0107] Flexible mode switching: when braking, the main shaft 6 stops rotating, the hob is fixed, and linear rock breaking is simulated by the Y-axis feed of the numerical control machine tool; when releasing, the main shaft 6 drives the hob to rotate, and the switching time is less than 10 seconds;

[0108] Braking stability: the caliper 14 symmetrically clamps the brake disc 13, there is no eccentric load vibration during braking, and the speed fluctuation is less than 2%;

[0109] Compatibility: the brake disc 13 is designed integrally with the main shaft 6, and does not interfere with the normal operation of the speed reducer 4 and the shaft coupling 5.

[0110] The hob position adjusting unit comprises an open-ended box body 16, and the front side wall of the box body 16 is fixedly connected with the rear end of the main shaft 6 through a connecting disc 17 and is driven to rotate by the main shaft 6;

[0111] A lead screw 18 is arranged in the box body 16, the lead screw 18 extends in the left-right direction, and both ends of the lead screw 18 are rotatably connected with the left and right side walls of the box body 16 through bearings;

[0112] A worm wheel 19 is fixedly installed at the middle part of the lead screw 18, the worm wheel 19 is meshingly connected with a worm 20, and the upper and lower ends of the worm 20 are rotatably connected with the upper wall of the box body 16 and the bottom wall of the box body 16 respectively; the upper end of the worm 20 extends out of the top wall of the box body 16 and the extended part serves as a hand holding part 21;

[0113] The screw rod 18 on the left and right sides of the worm gear 19 is symmetrically screwed with a screw rod slider 22, and the rotation direction of the screw thread on the screw rod 18 on both sides of the worm 20 is opposite; the screw rod slider 22 corresponds to the hobbing module one by one and is used to drive the hobbing module;

[0114] When the screw rod 18 rotates, it drives the two screw rod sliders 22 to synchronously approach or synchronously move away from the worm gear 19.

[0115] Technical advantages:

[0116] Convenient spacing adjustment: manually rotating the pinch part 21 can drive the two screw rod sliders 22 to approach or move away from each other, and the spacing adjustment is very convenient, without the need to replace parts, and the working condition switching time is shortened by more than 60%.

[0117] High-precision adjustment: the transmission ratio of the worm gear 19 and the worm 20 is ≥20:1, and the manual adjustment of the hob spacing accuracy is ±0.1mm;

[0118] Self-locking anti-deviation: the reverse self-locking feature of the worm gear 19 and the worm 20 ensures that the hob spacing is fixed during the experiment, and the vibration displacement is less than 0.05mm;

[0119] The rear top wall of the box body 16 is connected backward with an upper sliding rail 23, and the upper sliding rail 23 is slidably embedded with an upper sliding groove 24 through a dovetail groove structure; the rear bottom wall of the box body 16 is connected backward with a lower sliding rail 25, and the lower sliding rail 25 is slidably embedded with a lower sliding groove 26 through a dovetail groove structure;

[0120] The hobbing module comprises a tool holder front plate 27, the upper end of the tool holder front plate 27 is fixedly connected with the rear wall surface of the upper sliding groove 24 through screws, and the lower end of the tool holder front plate 27 is fixedly connected with the rear wall surface of the lower sliding groove 26 through screws; the middle part of the tool holder front plate 27 is fixedly connected forward with the screw rod slider 22; the tool holder front plate 27 is fixedly connected backward with a tool holder 28, the tool holder 28 is installed with a hob 29, and the hob 29 protrudes backward from the tool holder 28.

[0121] The hobbing module is convenient and fast to replace, and only needs to remove or tighten the screws between the tool holder front plate 27 and the sliding groove rear wall surface to remove or replace the hobbing module.

[0122] The upper sliding rail 23 and the lower sliding rail 25 constrain the hobbing module and the screw rod slider 22 from rotating, and when the screw rod 18 rotates, it will naturally drive the two screw rod sliders 22 and the two hobbing modules to approach or move away from each other.

[0123] The vertical position adjusting structure of the hydraulic oil cylinder 8 in the confining pressure loading unit comprises multiple rows of positioning holes 30 arranged on the left and right legs of the portal frame 7, and the positioning holes 30 in each row are uniformly spaced vertically; the hydraulic oil cylinder 8 is fixed with the positioning holes 30 through bolts, and is locked after adjusting the height.

[0124] By connecting the hydraulic cylinder 8 with the positioning hole 30 at different heights, the vertical height of the hydraulic cylinder 8 can be conveniently adjusted to adapt to the confining pressure loading needs of rock samples of different sizes.

[0125] The three-way force gauge 31 is fixedly connected between the cutter holder front plate 27 and the cutter holder 28 through bolts; the three-way force gauge 31 is connected with a wireless communication module, the box body 16 or the cutter holder 28 is connected with a storage battery, the three-way force gauge 31 and the wireless communication module are respectively connected with the storage battery, the three-way force gauge 31 is used for monitoring three-way stress data of the hob 29, and the wireless communication module is used for communication of a control system of the numerical control machine tool.

[0126] The three-way force gauge 31 can synchronously measure the radial force (Fx), the tangential force (Fy) and the axial force (Fz) of the hob 29 when the hob 29 breaks rocks, and is transmitted in real time to the control system of the numerical control machine tool through the wireless communication module, so as to provide a basis for dynamically adjusting the feeding speed or the confining pressure parameter.

[0127] The support 15 is fixedly connected with a positioning ring 32, and the circumferential inner surface of the positioning ring 32 is recessed to form an annular track groove 33; the box body 16 is connected with a roller 34 at both ends of the front surface, and the roller 34 is embedded in the track groove 33 and is in rolling cooperation with the track groove 33.

[0128] The positioning ring 32 defines the rotation track of the box body 16, and improves the stability of the rotation of the hob 29 and the accuracy of the rotation track.

[0129] The torque speed sensor 35 is installed on the shaft coupling 5, and the circuit of the torque speed sensor 35 is connected with the control system of the numerical control machine tool.

[0130] The working process of the utility model is:

[0131] I. Experimental preparation stage

[0132] 1. Rock sample installation and confining pressure loading

[0133] The rock sample is fixed on the workbench 1 of the numerical control machine tool, and the L-shaped baffle 11 and the reinforcing rib of the rock sample bearing module ensure the stability of the rock sample in the front and rear directions during the experiment.

[0134] According to the size of the rock sample, the height of the portal frame 7 of the confining pressure loading module is adjusted: through the multiple rows of positioning holes 30 on the left and right legs of the portal frame 7, the hydraulic cylinder 8 is fixed at a suitable position, and the confining pressure applying plate 9 of the corresponding size is installed.

[0135] Start hydraulic cylinder 8, through the universal joint 10 and confining pressure exerted plate 9 on the rock sample to apply three-dimensional confining pressure, simulate the stress state of the actual formation rock mass. Flexible material layer (such as rubber layer) to ensure uniform transmission of pressure, avoid local stress concentration.

[0136] 2、Roller cutter 29 system configuration

[0137] According to the experimental requirements, select full size cutter 29 or scaled cutter 29, install into the cutter holder 28.

[0138] Manual rotation hand pinch 21, through the worm gear 19 worm 20 drive screw block 22 symmetrical movement, adjust the distance between the two cutter 29 (precision ± 0.1mm). The self locking function of the worm gear 19 worm 20 ensures that the distance between the two cutter 29 is fixed during the experiment.

[0139] II、Experimental parameter setting

[0140] Mode selection

[0141] Rotary rock breaking mode: release the brake module, power device 3 (motor) through the speed reducer drive module to drive the spindle 6 rotation, drive the cutter 29 around the shaft rotation.

[0142] Linear rock breaking mode: start the brake module, caliper 14 brake disc 13 dead, spindle 6 stop, cutter 29 fixed; through the Y axis feed motion of numerical control machine tool workbench 1 to simulate linear rock breaking.

[0143] Motion control

[0144] Using the X / Y axis micron level movement precision of numerical control machine tool, set the workbench 1 feed speed, trajectory direction and rock breaking depth, simulate the dynamic behavior of TBM tunneling.

[0145] Through the numerical control system linkage control speed reducer 4 and power source, realize the dynamic matching of rotating speed-torque, cover the whole stratum simulation demand from hard rock to soft rock.

[0146] III、Experimental execution and data acquisition

[0147] Rock breaking process

[0148] Start power device 3, cutter 29 in rotary or linear mode to rock sample for rock breaking.

[0149] Confining pressure loading module real-time maintenance of three-dimensional confining pressure, ensure the stability of the rock sample under the compression stress state.

[0150] Numerical control machine tool cutting fluid application system simulates the TBM tunneling environment, to the rock sample spray cooling water.

[0151] Data monitoring

[0152] Three-way force gauge 31 measures the radial force (Fx), tangential force (Fy), axial force (Fz) of the cutter 29 in real time, and transmits the data to the numerical control system through a wireless communication module.

[0153] Torque and speed sensor 35: monitors the speed and torque of the main shaft 6, and synchronously feeds the data to the control system for analysis of rock breaking energy consumption and data monitoring.

[0154] Numerical control system of numerical control machine tool: records the displacement accuracy (deviation <0.2mm) of the workbench 1, the stress distribution (error ≤5%) of the confining pressure, and other key parameters.

[0155] Four, post-experiment processing and analysis

[0156] Working condition switching and module replacement

[0157] Loosen the brake module and switch the rock breaking mode (switching time <10 seconds).

[0158] By disassembling the screws of the cutter holder front plate 27, different size cutter modules (full size / reduced size) can be quickly replaced to adapt to new experimental requirements.

[0159] Data analysis

[0160] Combined with three-way force, torque, speed and displacement data, the rock breaking mechanism (such as stress superposition effect, rock breaking mode) and wear mechanism of the cutter 29 are analyzed.

[0161] Optimize the cutter layout, speed-torque matching, confining pressure parameters, etc., to provide experimental basis for improving the service life and tunneling efficiency of TBM cutters.

[0162] The present application utilizes the micron-level control and modular design of numerical control machine tools to support full-size / reduced-size cutter 29 experiments, breaking through the limitations of traditional platforms. The present application precisely simulates the stress of surrounding rock and multi-cutter rock breaking scenarios through three-way confining pressure loading and the synergistic effect of double cutters 29.

[0163] The worm gear 19 and the worm 20 are manually adjusted to adjust the distance between the cutters 29, and the working condition switching time is shortened by more than 60%.

[0164] The present application integrates the high-precision control of numerical control machine tools, modular cutter 29 systems and three-dimensional confining pressure loading technology, realizes full-condition simulation and efficient data acquisition of TBM cutter 29 rock breaking experiments, and provides a high-fidelity experimental platform for cutter optimization and engineering application.

[0165] The above examples are only used to illustrate but not to limit the technical solutions of the present application. Although the present application is described in detail with reference to the above examples, it should be understood by those skilled in the art that the present application can still be modified or equivalently replaced without departing from the spirit and scope of the present application, and any modification or partial replacement should be covered in the scope of the claims of the present application.

Claims

1. A TBM roller cutter rock breaking experimental platform based on a numerical control machine tool, comprising a worktable fixed on the numerical control machine tool, characterized in that: The workbench is provided with a confining pressure loading unit, which is used for fixing the rock sample and applying confining pressure simulating the formation stress to the rock sample; The confining pressure loading unit is opposite to the cutter system, the cutter system has a bearing table, the bearing table is provided with a power device, the output shaft of the power device is connected with a speed reducer, the output shaft of the speed reducer is connected with a main shaft through a shaft coupling, the main shaft is provided with a brake unit, the main shaft is connected with a cutter position adjusting unit, the cutter position adjusting unit is connected with two cutter modules, the two cutter modules are respectively provided with cutters opposite to the confining pressure loading unit; the cutter position adjusting unit is used for adjusting the distance between the two cutters.

2. The TBM roller cutter rock breaking experiment platform based on a CNC machine tool according to claim 1, characterized in that: The confining pressure loading unit comprises a portal frame, three hydraulic cylinders and three confining pressure applying plates; The portal frame is fixed on the workbench, and the hydraulic cylinders correspond to the three confining pressure applying plates one by one; The three hydraulic cylinders are respectively vertically installed on the top beam and the inner sides of the left and right legs of the portal frame, the piston rods of the hydraulic cylinders are hinged to the confining pressure applying plates through universal joints, and the inner surfaces of the confining pressure applying plates are all provided with flexible material layers; The confining pressure applying plates are used for adhering to the surface of the rock sample and uniformly transmitting confining pressure during work; An L-shaped baffle is installed on the workbench behind the confining pressure loading unit, the vertical plate of the L-shaped baffle faces forward and is used for positioning the rear end position of the rock sample, the horizontal plate of the L-shaped baffle is fixedly connected with the workbench through bolts, and a diagonal brace is fixedly connected between the vertical plate and the horizontal plate of the L-shaped baffle.

3. The TBM roller cutter rock breaking experimental platform based on CNC machine tools according to claim 1, characterized in that: The brake unit comprises a brake disc and a caliper; The brake disc is fixed to the end of the main shaft and rotates synchronously with the main shaft; The caliper is fixed on the bearing table through a support, and the brake pad of the caliper is parallel to the contact surface of the brake disc; The caliper is driven by hydraulic or pneumatic drive to realize the locking or releasing of the brake disc.

4. The TBM cutter rock breaking experimental platform based on a numerical control machine tool according to claim 1, characterized in that: the direction of the main shaft towards the confining pressure loading unit is the rear direction, the cutter position adjusting unit comprises an open-ended box body, the rear end of the box body is fixedly connected with the rear end of the main shaft through a connecting disc and is driven to rotate by the main shaft; a lead screw is arranged in the box body and extends along the left-right direction, and the two ends of the lead screw are respectively rotationally connected with the left and right side walls of the box body through bearings; a worm wheel is fixedly installed on the middle part of the lead screw, the worm wheel is meshingly connected with a worm, and the upper and lower ends of the worm are rotationally matched with the upper wall and the bottom wall of the box body; the upper end of the worm extends out of the top wall of the box body and serves as a hand holding part; symmetrical screw nuts are connected with the lead screws on the left and right sides of the worm wheel, the rotation directions of the threads on the lead screws on the left and right sides of the worm wheel are opposite; the screw nuts correspond to the cutter modules and are used for driving the cutter modules; when the lead screw rotates, the two screw nuts are driven to synchronously move towards or away from the worm wheel along the axial direction.

5. The TBM cutter rock breaking experimental platform based on a numerical control machine tool according to claim 4, characterized in that: an upper slide rail is connected to the rear end top wall of the box body, the upper slide rail is slidably connected with an upper slide groove through a dovetail groove structure; a lower slide rail is connected to the rear end bottom wall of the box body, and the lower slide rail is slidably connected with a lower slide groove through a dovetail groove structure. The hob module comprises a cutter holder front plate, the upper end of the cutter holder front plate is fixedly connected to the rear wall surface of the upper sliding groove by screws, and the lower end of the cutter holder front plate is fixedly connected to the rear wall surface of the lower sliding groove by screws; the middle part of the cutter holder front plate is fixedly connected to the screw sliding block forwardly; the cutter holder is fixedly connected to the rear of the cutter holder front plate, and the hob is installed in the cutter holder and protrudes rearward out of the cutter holder.

6. The CNC machine tool based TBM roller cutter rock breaking experiment platform according to claim 2, characterized in that: The vertical position adjusting structure of the hydraulic oil cylinder in the confining pressure loading unit comprises multiple rows of positioning holes arranged on the left and right legs of the portal frame, and the positioning holes are evenly and vertically spaced. The hydraulic oil cylinder is fixed with the positioning holes by bolts, and is locked after the height is adjusted.

7. The CNC machine tool based TBM roller cutter rock breaking experiment platform according to claim 4, characterized in that: A three-way force gauge is fixedly connected between the cutter holder front plate and the cutter holder by bolts; a wireless communication module is connected to the three-way force gauge, a battery is connected to the box or the cutter holder, the three-way force gauge and the wireless communication module are respectively connected to the battery, the three-way force gauge is used for monitoring three-way force data of the hob, and the wireless communication module is used for communication of the control system of the numerical control machine tool.

8. The CNC machine tool based TBM roller cutter rock breaking experiment platform according to claim 4, characterized in that: The support is fixedly connected to a positioning ring rearward, and an annular track groove is recessed in the circumferential inner surface of the positioning ring. Rollers are connected to the front surface of the box at both ends, the rollers are embedded in the track groove and rollingly cooperate with the track groove.

9. The CNC machine tool based TBM roller cutter rock breaking experiment platform according to claim 7, characterized in that: A torque and rotating speed sensor is installed on the coupling, and the circuit of the torque and rotating speed sensor is connected to the control system of the numerical control machine tool.

Images