Rock dynamic impact experiment device capable of controlling temperature in real time

Abstract

The invention relates to the technical field of rock mechanics experiments, in particular to a real-time temperature-controllable rock dynamic impact experiment device which comprises a test box and a placement table, an air cylinder is mounted at the top end of the test box, a guide rod is mounted at the top end in the test box, and a detection mechanism is arranged on the surface of the guide rod. The detection mechanism comprises an impact plate sliding on the outer wall of the guide rod, an air conveying groove is formed in the impact plate, and a high-pressure air pipe is inserted into the back face of the impact plate. High-pressure airflow in the air conveying groove is sprayed out through air outlet holes, so that a conversion groove communicated with the top end of the air conveying groove forms enough air pressure to push the piston rod and the indication rod to keep static; a worker can intuitively judge whether the surface of the rock sample has defects by observing whether the indicating rod moves or not, so that inaccuracy of experimental data caused by unevenness of the surface of the sample is avoided, real impact mechanical characteristics of rock are reflected by data, and the reliability of experimental results is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of rock mechanics experiment, and particularly relates to a rock dynamic impact experiment device capable of real-time temperature control. BACKGROUND

[0002] In the field of rock mechanics research, the mechanical properties of rock under dynamic impact load are key basic data for evaluating the stability of geotechnical engineering, the safety of tunnel excavation, the efficiency of mineral resource exploitation, and geological disaster warning. With the expansion of engineering construction to deep high stress and complex temperature environment, the influence of the temperature conditions on the dynamic mechanical behavior of rock becomes more and more significant. Therefore, rock dynamic impact experiments under different temperature environments have become one of the core needs of current research.

[0003] However, in the traditional device, only the size of the rock sample is adjusted before the impact experiment, and the potential defects such as the flatness of the sample surface and the internal micro-cracks are not effectively detected. Since the rock sample surface may have protrusions, depressions or micro-cracks, these defects will cause the impact load to concentrate or the stress to be unevenly transmitted during the dynamic impact process, resulting in a large deviation between the impact strength, deformation and other data measured in the experiment and the real mechanical properties of the rock.

[0004] Therefore, the present application provides a rock dynamic impact experiment device capable of real-time temperature control to solve the above problems and improve the practical value. SUMMARY

[0005] The present application aims to solve the problems in the prior art and provides a rock dynamic impact experiment device capable of real-time temperature control.

[0006] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: a rock dynamic impact experiment device capable of real-time temperature control, comprising a test box and a placement table, a gas cylinder is installed at the top end of the test box, a guide rod is installed at the inner top end of the test box, a detection mechanism is arranged on the surface of the guide rod, the detection mechanism comprises an impact plate sliding on the outer wall of the guide rod, a gas conveying groove is formed in the inner part of the impact plate, a high-pressure gas pipe is inserted into the back surface of the impact plate, a conversion groove is communicated with the top end of the gas conveying groove, a piston rod is slidingly arranged in the inner part of the conversion groove, a sealing plate is slidingly arranged at the bottom end of the gas conveying groove, a gas outlet hole is formed at the bottom end of the impact plate, and an indicating rod is installed at the top end of the piston rod.

[0007] The inside of the test box is provided with a temperature control mechanism, the temperature control mechanism comprises a mixing pipe installed in the test box, the two ends of the mixing pipe are respectively communicated with a cold air pipe and a hot air pipe, the surfaces of the cold air pipe and the hot air pipe are provided with temperature adjusting assemblies, the top end of the impact plate is inserted with a gas conveying pipe communicated with the mixing pipe, the inside of the impact plate is provided with a gas conveying groove A, and the bottom end of the impact plate is welded with a gas jet ring.

[0008] The inside of the impact plate is provided with a reverse thrust mechanism, the reverse thrust mechanism comprises an annular groove arranged in the inside of the impact plate, the surface of the impact plate is provided with a gas jet hole, and the gas conveying groove B is communicated between the conversion groove and the gas jet hole.

[0009] The upper side of the placing table is provided with a cleaning mechanism.

[0010] Preferably, the surface of the impact plate is provided with a scale line, one side of the indicating rod is provided with an indicating needle, and the surface of the piston rod is penetrated and installed with a one-way valve.

[0011] Preferably, the bottom end of the sealing plate is provided with a first spring, and the bottom end of the first spring is fixedly connected with the inner wall of the gas conveying groove.

[0012] Preferably, the temperature adjusting assembly comprises a control valve installed on the outer wall of the cold air pipe and the hot air pipe, one side of the control valve is rotatably provided with a valve rod, and one side of the impact plate is welded with a rack engaged with the valve rod.

[0013] Preferably, the gas jet hole is conical, and the diameter of the gas jet hole gradually decreases along the vertical direction of the impact plate.

[0014] Preferably, the cleaning mechanism comprises a spray pipe installed above the impact plate, the outer wall of the spray pipe is communicated with a telescopic pipe, the inside of the top end of the telescopic pipe is installed with a mounting bracket, the opening end of the telescopic pipe is slidably provided with a sealing ball, a second spring is fixedly installed between the mounting bracket and the sealing ball, the side wall of the mixing pipe is communicated with a butt joint pipe, and the opening end of the butt joint pipe is installed with a jacking rod.

[0015] Preferably, the upper end of the impact plate is provided with a gas collecting hood, the outer side of the impact plate is installed with a rectangular shell, and the gas collecting hood and the rectangular shell are communicated with a connecting pipe.

[0016] Preferably, the output end of the air cylinder is installed with an electromagnet A, and the top end of the impact plate is installed with an electromagnet B through a supporting rod.

[0017] Preferably, the inner wall of the gas jet ring is inclined, a plurality of gas discharge holes are arranged in the inner wall of the gas jet ring, and the gas jet ring is communicated with the gas conveying groove A.

[0018] Compared with the prior art, the beneficial effects of the present application are:

[0019] 1. In this invention, the high-pressure airflow inside the gas delivery channel flows downward along the channel and is directly ejected through the outlet. Since most of the high-pressure airflow is discharged through the outlet, the conversion channel connected to the top of the gas delivery channel cannot form sufficient air pressure to push the piston rod. The piston rod, which is slidably installed inside the conversion channel, will not move upward, and the indicator rod installed at the top of the piston rod will also remain stationary. By observing whether the indicator rod moves, the staff can intuitively judge whether there are defects on the surface of the rock sample. This effectively avoids the problem of inaccurate test data during the experiment due to uneven rock sample surface, ensuring that the experimental data can truly reflect the mechanical properties of the rock under impact and improving the reliability of the experimental results.

[0020] 2. This invention uses an impact plate that moves along the surface of a guide rod from a lower to a higher position to complete impact tests of different intensities. As the impact plate gradually rises to the highest impact position, the rack moves upward synchronously with the impact plate. The movement of the rack drives the valve rod to rotate, and the rotation of the valve rod can precisely adjust the opening and closing of the control valves on the outer walls of the cold air pipe and the hot air pipe. The opening degree of the control valve on the cold air pipe gradually increases, and the opening degree of the control valve on the hot air pipe gradually decreases, so that the amount of cold air entering the mixing pipe gradually exceeds the amount of hot air. The temperature of the airflow output from the mixing pipe gradually decreases, thereby achieving a smooth transition from room temperature to a low temperature environment. The automatic temperature control adjustment is completed during the movement of the impact plate, so as to provide a precise and stable temperature environment for the rock sample in real time according to the experimental requirements, without the need for frequent manual intervention in the temperature control process. This meets the testing requirements of dynamic rock impact experiments under low temperature conditions and improves the flexibility and accuracy of the experiment.

[0021] 3. This invention, as the impact plate begins to move downwards, allows airflow to enter the annular groove inside the impact plate along the air delivery groove B. The airflow then exits upwards through multiple sets of air jets on the surface of the impact plate. This upward airflow generates a downward thrust on the impact plate, which, combined with the plate's own weight, further increases the downward acceleration of the impact plate, resulting in a faster descent and a stronger impact force on the rock sample. This provides auxiliary acceleration to the descent speed of the impact plate. In cases where the overall height of the test platform is relatively low, the impact force generated by simple free fall is insufficient to meet experimental requirements. The high-speed airflow thrust effectively adjusts the descent acceleration of the impact plate, compensating for the impact force deficiency caused by insufficient height and avoiding experimental data deviations due to insufficient or unstable impact force from simple free fall. This further improves the accuracy and reliability of the dynamic rock impact experiment. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 Fig. 1 is a schematic diagram of the internal structure of the present application;

[0024] Figure 3 Fig. 2 is a schematic diagram of the sectional structure of the impact plate of the present application;

[0025] Figure 4 Fig. 3 is a schematic diagram of the internal structure of the present application; Figure 3 Fig. 4 is a schematic diagram of the enlarged structure of part A of the present application;

[0026] Figure 5 Fig. 5 is a schematic diagram of the sectional structure of the impact plate of the present application;

[0027] Figure 6 Fig. 6 is a schematic diagram of the temperature control mechanism of the present application;

[0028] Figure 7 Fig. 7 is a schematic diagram of part of the structure of the present application;

[0029] Figure 8 Fig. 8 is a schematic diagram of part of the structure of the present application;

[0030] Figure 9 Fig. 9 is a schematic diagram of the cleaning mechanism of the present application

[0031] Figure 10 Fig. 10 is a schematic diagram of the internal structure of the present application; Figure 9 Fig. 11 is a schematic diagram of the enlarged structure of part B of the present application.

[0032] Fig. 12 is a schematic diagram of the internal structure of the present application;

[0033] 1, test box; 2, placing table; 3, air cylinder; 4, detection mechanism; 41, impact plate; 42, air conveying groove; 43, conversion groove; 44, piston rod; 45, high-pressure air pipe; 46, sealing plate; 47, air outlet hole; 48, indicating rod; 49, one-way valve; 5, temperature control mechanism; 51, cold air pipe; 52, hot air pipe; 53, mixing pipe; 54, control valve; 55, valve rod; 56, rack; 57, air conveying pipe; 58, air jet ring; 59, air conveying groove A; 7, reverse thrust mechanism; 71, annular groove; 72, air jet hole; 73, air conveying groove B; 74, air collecting cover; 75, rectangular shell; 76, connecting pipe; 8, cleaning mechanism; 81, jet pipe; 82, telescopic pipe; 83, mounting frame; 84, sealing ball; 85, butt joint pipe; 86, ejector rod; 9, electromagnet A; 10, electromagnet B; 11, guide rod. DETAILED DESCRIPTION

[0034] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0035] Referring to Figures 1 to 10 As shown in the figure, the present application provides a rock dynamic impact experiment device capable of real-time temperature control, which comprises a test box 1 and a placement table 2. A gas cylinder 3 is installed at the top end of the test box 1. A guide rod 11 is installed at the inner top end of the test box 1. A detection mechanism 4 is arranged on the surface of the guide rod 11. The detection mechanism 4 comprises an impact plate 41 sliding on the outer wall of the guide rod 11. A gas conveying groove 42 is formed in the impact plate 41. A high-pressure gas pipe 45 is inserted into the back of the impact plate 41. A conversion groove 43 is communicated with the top end of the gas conveying groove 42. A piston rod 44 is slidingly arranged in the conversion groove 43. A sealing plate 46 is slidingly arranged at the bottom end of the gas conveying groove 42. An air outlet hole 47 is formed at the bottom end of the impact plate 41. An indicating rod 48 is installed at the top end of the piston rod 44.

[0036] It should be noted that when the rock impact experiment is needed, the staff needs to place the rock sample to be tested on the surface of the placement table 2 in the test box 1. Then, the gas cylinder 3 is started. The output end of the gas cylinder 3 drives the impact plate 41 to slide vertically downward along the guide rod 11 installed at the inner top end of the test box 1, until the bottom end of the impact plate 41 completely abuts against the upper end surface of the rock sample. At this time, the impact plate 41 and the rock sample form an initial state of close contact.

[0037] When the impact plate 41 abuts against the rock sample, the high-pressure gas pump outside is used to convey high-pressure gas flow into the high-pressure gas pipe 45 inserted into the back of the impact plate 41. The high-pressure gas flow enters the gas conveying groove 42 formed in the impact plate 41 through the high-pressure gas pipe 45. At the moment when the impact plate 41 abuts against the rock sample, the sealing plate 46 slidingly arranged at the bottom end of the gas conveying groove 42 will first contact the surface of the rock sample. The rock sample generates an upward counteracting force on the sealing plate 46. Under the action of the force, the sealing plate 46 slides upward along the inner wall of the gas conveying groove 42, thereby unblocking the passage between the gas conveying groove 42 and the air outlet hole 47 at the bottom end of the impact plate 41, so that the gas conveying groove 42 and the air outlet hole 47 form a communication state.

[0038] At this time, if the surface of the rock sample to be detected has protrusions, depressions and other defects, the high-pressure gas flow in the gas conveying groove 42 will flow downward along the channel of the gas conveying groove 42 and be directly sprayed out through the gas outlet hole 47. Since most of the high-pressure gas flow is discharged through the gas outlet hole 47, the gas pressure in the conversion groove 43 connected to the top end of the gas conveying groove 42 cannot form enough force to push the piston rod 44. The piston rod 44 slidingly arranged in the conversion groove 43 will not move upward, and the indicating rod 48 mounted at the top end of the piston rod 44 also remains in a stationary state. Workers can directly judge whether the surface of the rock sample has defects by observing whether the indicating rod 48 moves, effectively avoiding the problem that the detection data accuracy is not accurate during the experiment due to the uneven surface of the rock sample, ensuring that the experimental data can truly reflect the mechanical properties of the rock under impact, and improving the reliability of the experimental results.

[0039] The inside of the test box 1 is provided with a temperature control mechanism 5, which includes a mixing pipe 53 installed inside the test box 1. The two ends of the mixing pipe 53 are respectively communicated with a cold air pipe 51 and a hot air pipe 52. The surfaces of the cold air pipe 51 and the hot air pipe 52 are respectively provided with temperature adjusting assemblies. The top end of the impact plate 41 is inserted with a gas conveying pipe 57 communicated with the mixing pipe 53. The inside of the impact plate 41 is provided with a gas conveying groove A 59. The bottom end of the impact plate 41 is welded with a gas jet ring 58.

[0040] It should be noted that after the preliminary positioning of the rock sample is completed, if the surface of the rock to be detected has no protrusions, depressions and other defects, the bottom end of the impact plate 41 will form a tight sealing state with the upper end surface of the rock. At this time, the high-pressure gas flow conveyed by the external high-pressure gas pump through the high-pressure gas pipe 45 to the gas conveying groove 42 inside the impact plate 41 cannot be discharged through the gas outlet hole 47, but can only accumulate continuously inside the gas conveying groove 42, causing the gas pressure inside the gas conveying groove 42 to continue to increase. As the gas pressure gradually rises, the resulting thrust will push the piston rod 44 inside the conversion groove 43 to move upward along the inner wall of the conversion groove 43. When the piston rod 44 moves to the maximum stroke, it will be separated from the blockage of the gas conveying groove A 59 inside the impact plate 41, and at the same time, it will form a blockage to the gas conveying groove B 73. At this time, the workers start the external cold air blower and hot air blower. The cold air blower sends cold air to the cold air pipe 51, and the hot air blower sends hot air to the hot air pipe 52. In the initial stage of the experiment, the device is set to have a slightly lower cold air volume than the hot air volume. In this way, the cold air and hot air entering the inside of the mixing pipe 53 will be fully mixed to form normal temperature air that meets the initial requirements of the experiment. The normal temperature air after mixing passes through the gas conveying pipe 57 inserted at the top end of the impact plate 41 and communicated with the mixing pipe 53, and is conveyed to the upper area of the conversion groove 43. Since the piston rod 44 is internally provided with a one-way valve 49, the gas flow can smoothly pass through the one-way valve 49 to the lower part of the conversion groove 43, and then be conveyed to the inside of the gas jet ring 58 along the gas conveying groove A 59. Finally, it is uniformly blown to the surface of the rock to be detected through the exhaust holes in the inner wall of the gas jet ring 58, creating a stable initial temperature environment for the rock sample.

[0041] In the subsequent process of carrying out rock impact experiment, the impact plate 41 will move along the surface of the guide rod 11 from a lower position to a higher position to complete impact tests of different intensities. As the impact plate 41 gradually rises to the highest impact position, the rack 56 will move upward synchronously with the impact plate 41. The movement of the rack 56 will cause the valve rod 55 to rotate, and the rotation of the valve rod 55 can accurately adjust the opening and closing size of the control valve 54 on the outer wall of the cold air pipe 51 and the hot air pipe 52. The opening and closing degree of the control valve 54 on the cold air pipe 51 gradually increases, and the opening and closing degree of the control valve 54 on the hot air pipe 52 gradually decreases, so that the amount of cold air entering the mixing pipe 53 gradually exceeds the amount of hot air, the temperature of the airflow output by the mixing pipe 53 gradually decreases, and then the smooth transition from normal temperature to low temperature environment is realized. The automatic temperature control adjustment is completed during the movement of the impact plate 41, so that the rock sample can be provided with accurate and stable temperature environment in real time according to the experimental requirements, without frequent manual intervention in the temperature control process, meeting the test requirements of rock dynamic impact experiment under low temperature conditions, and improving the flexibility and accuracy of the experiment.

[0042] The inside of the impact plate 41 is provided with a counter thrust mechanism 7, which includes an annular groove 71 opened in the inside of the impact plate 41, and the surface of the impact plate 41 is provided with a gas injection hole 72, and the conversion groove 43 and the gas injection hole 72 are communicated with a gas supply groove B73;

[0043] It should be noted that when the rock to be detected reaches the specified temperature required by the experiment, the worker starts the air cylinder 3 at the top end of the test box 1. The output end of the air cylinder 3 drives the impact plate 41 to move upward along the internal top guide rod 11 until the impact plate 41 rises to the specified impact height preset by the experiment. During the process of the impact plate 41 rising to the specified height, the electromagnet A9 used to connect the output end of the air cylinder and the impact plate and the electromagnet B10 installed at the top end of the impact plate through the support rod are in the energized adsorption state to ensure that the impact plate 41 can stably rise with the output end of the air cylinder 3. When the impact plate 41 reaches the specified impact height, the worker turns off the power of the electromagnet A9 and the electromagnet B10, so that the adsorption force between them disappears. At this time, the impact plate 41 loses the upward pulling force and fixing force and starts to do free fall along the surface of the guide rod 11 under the action of its own gravity, and then impacts the rock sample placed on the lower placing table 2 to obtain the mechanical property data of the rock under the impact condition;

[0044] When the impact plate 41 starts to move downward, the staff synchronously closes the external high-pressure air pump, so that the channel originally conveying high-pressure gas to the back of the impact plate 41 is interrupted, the high-pressure air pipe no longer inputs high-pressure gas into the inside of the air conveying groove 42, and the air pressure supporting the piston rod 44 to keep at the upper end of the conversion groove 43 gradually disappears, and the piston rod 44 starts to move downward along the inner wall of the conversion groove 43 under its own gravity, and when the piston rod 44 drops to a certain position, the air conveying groove B73 is no longer blocked, so that the conversion groove 43 and the air conveying groove B73 are smoothly connected, and the continuously mixed gas flow in the mixing pipe 53 is continuously conveyed to the conversion groove 43 area through the air conveying pipe 57, and the gas flow enters the annular groove 71 opened in the impact plate 41 through the air conveying groove B73, and then is sprayed upward through the multiple groups of air injection holes 72 opened on the surface of the impact plate 41. Since the direction of the gas flow sprayed by the air injection hole 72 is upward, according to the principle of force interaction, when the gas flow is sprayed upward, a downward counterforce is generated on the impact plate 41, and the counterforce and the gravity of the impact plate 41 are superimposed on the impact plate 41, so that the acceleration of the downward movement of the impact plate 41 is further increased, the downward speed is faster, and finally the impact force acting on the rock sample is stronger, so that the downward acceleration of the impact plate is accelerated, and the impact force is difficult to meet the experimental requirements when the overall height of the test bench 1 is designed to be low. Through the action of the high-speed air flow counterforce, the downward acceleration of the impact plate can be effectively adjusted, the impact force defect caused by the insufficient height is compensated, the experimental data deviation caused by the insufficient or unstable impact force of the pure free fall is avoided, and the accuracy and reliability of the rock dynamic impact experiment are further improved.

[0045] The upper side of the placement table 2 is provided with a cleaning mechanism 8.

[0046] As shown in Figures 4 to 5 The surface of the impact plate 41 is provided with a scale, one side of the indicating rod 48 is provided with an indicating needle, and the surface of the piston rod 44 is provided with a one-way valve 49. The scale on the surface of the impact plate 41 and the indicating needle on one side of the indicating rod 48 cooperate with each other, so that the staff can intuitively read the movement amplitude of the piston rod 44, and further judge the change of the air pressure in the air conveying groove 42 and whether there is a defect on the surface of the rock. The one-way valve 49 installed on the surface of the piston rod 44 can realize one-way flow of the gas flow, so as to ensure that the temperature-controlled gas flow conveyed by the mixing pipe 53 can stably flow to the air conveying groove A59 or the air conveying groove B73, and avoid interference of the reverse flow of the gas flow with the normal operation of the device.

[0047] As shown in Figure 4 The bottom end of the sealing plate 46 is provided with a first spring, and the bottom end of the first spring is fixedly connected with the inner wall of the air conveying groove 42.

[0048] As shown in Figure 6As shown, the temperature adjusting assembly comprises a control valve 54 mounted on the outer wall of the cold air pipe 51 and the hot air pipe 52, and a valve rod 55 is rotatably arranged on one side of the control valve 54. A rack 56 is welded on one side of the impact plate 41 and engages with the valve rod 55.

[0049] As shown in Figure 4 As shown, the air injection hole 72 is conical, and the diameter of the air injection hole 72 gradually decreases in the vertical direction of the impact plate 41. The conical structure can reduce the diffusion loss of the airflow in the injection hole, improve the utilization rate of the airflow, and ensure the stability of the reverse thrust effect.

[0050] As shown in Figures 9 to 10 As shown, the cleaning mechanism 8 comprises a spray pipe 81 mounted above the impact plate 41. The outer wall of the spray pipe 81 is connected with a telescopic pipe 82. The top end of the telescopic pipe 82 is internally mounted with a mounting bracket 83. The opening end of the telescopic pipe 82 is slidably provided with a sealing ball 84. A second spring is fixedly installed between the mounting bracket 83 and the sealing ball 84. The side wall of the mixing pipe 53 is connected with a butt joint pipe 85. The opening end of the butt joint pipe 85 is internally mounted with a top rod 86.

[0051] It should be noted that after the impact experiment is completed, the electromagnet A9 and the electromagnet B10 are energized, and the air cylinder 3 drives the impact plate 41 to move upwards, so that the top end of the telescopic pipe 82 is inserted into the inside of the butt joint pipe 85. At this time, the top rod 86 inside the butt joint pipe 85 pushes the sealing ball 84 inside the telescopic pipe 82 to shrink inward, so that the telescopic pipe 82 is connected with the butt joint pipe 85. Then, part of the airflow in the mixing pipe 53 enters the inside of the telescopic pipe 82 through the butt joint pipe 85, and is sprayed to the surface of the rock through the spray pipe 81. The sprayed airflow can generate strong blowing force on the debris, powder and other impurities remaining on the surface of the rock after the impact experiment, so as to strip and blow away these impurities from the surface of the rock and the placement table 2 area, thereby achieving efficient cleaning of the surface of the rock and the experimental area, effectively preventing the interference of residual debris on the accuracy of subsequent experimental detection data, and further improving the coherence and reliability of the experimental process.

[0052] As shown in Figures 7 to 8 As shown, the upper end of the impact plate 41 is provided with a gas collecting hood 74, and the outer side of the impact plate 41 is provided with a rectangular shell 75. The gas collecting hood 74 and the rectangular shell 75 are connected by a connecting pipe 76.

[0053] As shown in Figure 7 As shown, the output end of the air cylinder 3 is provided with an electromagnet A9, and the top end of the impact plate 41 is provided with an electromagnet B10 through a support rod.

[0054] As shown in Figure 4 As shown, the inner wall of the air injection ring 58 is inclined, and a plurality of air exhaust holes are formed in the inner wall of the air injection ring 58. The air injection ring 58 is connected with the air supply groove A59.

[0055] It should be noted that when the gas flow sprayed by the air jet hole 72 moves upward, the gas flow is collected along the inner wall of the gas collecting cover 74 to the inside, and then the gas flow is transported to the inside of the rectangular shell 75 through the connecting pipe 76, and finally discharged through the air outlet at the bottom of the rectangular shell 75, forming a protective air curtain. The rock is subjected to a strong impact force and may produce splashing stones. The air flow resistance generated by the air curtain can effectively block the movement track of the stones, slow down the splashing speed of the stones, and avoid the damage caused by the impact of the stones on the inner wall of the test box 1. At the same time, the impact plate 41 will produce relatively obvious impact noise when impacting the rock, and the movement of the air flow of the protective air curtain can absorb and buffer the noise sound wave to a certain extent. The gas flow interacts with the sound wave during the flow process, consumes the energy of the sound wave, thereby reducing the noise intensity in the experiment to a certain extent, improving the acoustic conditions of the experimental environment, and reducing the influence of noise on the hearing of the workers.

[0056] Working principle: when the rock needs to be impacted, the worker needs to place the rock sample to be tested on the surface of the placing table 2 inside the test box 1, and then start the air cylinder 3. The output end of the air cylinder 3 drives the impact plate 41 to slide vertically downward along the guide rod 11 installed at the top end inside the test box 1, until the bottom end of the impact plate 41 completely abuts against the upper end surface of the rock sample. At this time, the impact plate 41 and the rock sample form an initial state of close contact.

[0057] When the impact plate 41 abuts against the rock sample, the high-pressure gas pump outside the test box 1 sends high-pressure gas flow into the high-pressure gas pipe 45 inserted into the back of the impact plate 41. The high-pressure gas flow enters the gas conveying groove 42 inside the impact plate 41 through the high-pressure gas pipe 45. At the moment when the impact plate 41 abuts against the rock sample, the sealing plate 46 slidably arranged at the bottom end of the gas conveying groove 42 will first contact the surface of the rock sample. The rock sample generates an upward counteracting force on the sealing plate 46. Under the action of the force, the sealing plate 46 slides upward along the inner wall of the gas conveying groove 42, thereby unblocking the passage between the gas conveying groove 42 and the gas outlet hole 47 at the bottom end of the impact plate 41, so that the gas conveying groove 42 and the gas outlet hole 47 form a communication state.

[0058] At this time, if there are protrusions, depressions and other defects on the surface of the rock sample to be tested, the high-pressure gas flow in the gas conveying groove 42 will flow downward along the passage of the gas conveying groove 42 and be directly sprayed out through the gas outlet hole 47. Since most of the high-pressure gas flow is discharged through the gas outlet hole 47, the gas pressure in the conversion groove 43 connected to the top end of the gas conveying groove 42 cannot form enough to push the piston rod 44. The piston rod 44 slidably arranged in the conversion groove 43 will not move upward, and the indicating rod 48 installed at the top end of the piston rod 44 also remains in a stationary state. The worker can directly judge whether there are defects on the surface of the rock sample by observing whether the indicating rod 48 moves.

[0059] When the preliminary positioning of the rock sample is completed, if the surface of the rock to be tested does not have protrusions, depressions or other defects, the bottom end of the impact plate 41 will form a tight sealing state with the upper end surface of the rock. At this time, the high-pressure gas flow delivered by the external high-pressure gas pump through the high-pressure gas pipe 45 to the gas delivery groove 42 inside the impact plate 41 cannot be discharged through the gas outlet hole 47, but can only continuously accumulate inside the gas delivery groove 42, causing the internal gas pressure of the gas delivery groove 42 to continuously increase. As the gas pressure gradually rises, the resulting thrust will push the piston rod 44 inside the conversion groove 43 to move upward along the inner wall of the conversion groove 43. When the piston rod 44 moves to the maximum stroke, it will be disconnected from the blocking of the gas delivery groove A 59 inside the impact plate 41, while blocking the gas delivery groove B 73. At this time, the operator starts the external air cooler and air heater. The air cooler delivers cold air to the cold air pipe 51, and the air heater delivers hot air to the hot air pipe 52. In the initial stage of the experiment, the device is set to have a slightly lower cold air volume than the hot air volume. In this way, the cold air and hot air entering the mixing pipe 53 will be fully mixed to form room temperature air that meets the initial requirements of the experiment. The room temperature air after mixing passes through the gas delivery pipe 57 inserted into the top end of the impact plate 41 and connected with the mixing pipe 53, and is delivered to the upper area of the conversion groove 43. Since the piston rod 44 is equipped with a one-way valve 49, the gas flow can smoothly pass through the one-way valve 49 to the lower part of the conversion groove 43, and then be delivered to the air jet ring 58 inside the gas delivery groove A 59. Finally, it is uniformly blown to the surface of the rock to be tested through the exhaust holes in the inner wall of the air jet ring 58, creating a stable initial temperature environment for the rock sample.

[0060] In the subsequent rock impact experiment, the impact plate 41 will move from a lower position to a higher position along the surface of the guide rod 11 to complete impact tests of different strengths. As the impact plate 41 gradually rises to the highest impact position, the rack 56 will move upward synchronously with the impact plate 41. The movement of the rack 56 will cause the valve rod 55 to rotate, and the rotation of the valve rod 55 can accurately adjust the opening and closing size of the control valve 54 on the outer wall of the cold air pipe 51 and the hot air pipe 52. The opening degree of the control valve 54 on the cold air pipe 51 gradually increases, and the opening degree of the control valve 54 on the hot air pipe 52 gradually decreases, so that the amount of cold air entering the mixing pipe 53 gradually exceeds the amount of hot air. The temperature of the gas flow output by the mixing pipe 53 gradually decreases.

[0061] When the rock to be detected reaches the specified temperature required for the experiment, the staff starts the air cylinder 3 at the top end of the test box 1, the output end of the air cylinder 3 drives the impact plate 41 to move upward along the guide rod 11 at the top end, until the impact plate 41 rises to the preset specified impact height, in the process of the impact plate 41 rising to the specified height, the electromagnet A9 previously used to connect the output end of the air cylinder and the impact plate and the electromagnet B10 installed at the top end of the impact plate through a support rod are in the energized adsorption state, to ensure that the impact plate 41 can stably follow the output end of the air cylinder 3 to rise, when the impact plate 41 reaches the specified impact height, the staff turns off the power of the electromagnet A9 and the electromagnet B10, so that the adsorption force between the two disappears, at this time the impact plate 41 loses the upward pulling force and fixing force, and under the action of its own gravity, it starts to do free fall along the surface of the guide rod 11, and then impacts the rock sample placed on the lower placing table 2 to obtain the mechanical property data of the rock under the impact condition;

[0062] At the same time when the impact plate 41 starts to move downward, the staff synchronously turns off the external high-pressure gas pump, so that the channel originally conveying high-pressure gas to the back of the impact plate 41 is interrupted, the high-pressure gas supply pipe no longer inputs high-pressure gas into the inside of the gas conveying groove 42, and as the gas inside the gas conveying groove 42 is no longer supplemented, the gas pressure that previously supported the piston rod 44 to keep at the upper end position of the conversion groove 43 gradually disappears, and the piston rod 44 starts to move downward along the inner wall of the conversion groove 43 under its own gravity, when the piston rod 44 descends to a certain position, it no longer blocks the gas conveying groove B73, so that the conversion groove 43 and the gas conveying groove B73 are smoothly connected, at this time the continuously mixed gas flow in the mixing pipe 53 is continuously conveyed to the conversion groove 43 area through the gas conveying pipe 57, the gas flow enters the annular groove 71 opened in the inside of the impact plate 41 along the gas conveying groove B73, and then is sprayed upward through the multiple groups of gas injection holes 72 opened on the surface of the impact plate 41, as the direction of the gas flow sprayed by the gas injection holes 72 is upward, according to the principle of force interaction, when the gas flow is sprayed upward, it will generate a downward counterforce on the impact plate 41, and the downward counterforce and the gravity of the impact plate 41 form superposition and jointly act on the impact plate 41, so that the acceleration of the impact plate 41 moving downward is further increased.

[0063] Finally, it should be noted that the above description is only a preferred embodiment of the present application and is not intended to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacement for some technical features, any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A rock dynamic impact experiment device capable of real-time temperature control, comprising a test box (1) and a placement table (2), a gas cylinder (3) is installed at the top end of the test box (1), characterized in that: The inside top end of the test box (1) is provided with a guide rod (11), the surface of the guide rod (11) is provided with a detection mechanism (4), the detection mechanism (4) comprises an impact plate (41) sliding on the outer wall of the guide rod (11), a gas conveying groove (42) is formed in the inside of the impact plate (41), a high-pressure gas pipe (45) is inserted into the back surface of the impact plate (41), the top end of the gas conveying groove (42) is communicated with a conversion groove (43), a piston rod (44) is slidingly arranged in the inside of the conversion groove (43), a sealing plate (46) is slidingly arranged at the bottom end of the gas conveying groove (42), a gas outlet hole (47) is formed in the bottom end of the impact plate (41), and an indicating rod (48) is arranged at the top end of the piston rod (44). The inside of the test box (1) is provided with a temperature control mechanism (5), the temperature control mechanism (5) comprises a mixing pipe (53) arranged in the inside of the test box (1), the two ends of the mixing pipe (53) are respectively communicated with a cold air pipe (51) and a hot air pipe (52), the surfaces of the cold air pipe (51) and the hot air pipe (52) are provided with temperature adjusting assemblies, the top end of the impact plate (41) is inserted with a gas conveying pipe (57) communicated with the mixing pipe (53), a gas conveying groove A (59) is formed in the inside of the impact plate (41), and a gas jet ring (58) is welded at the bottom end of the impact plate (41). The inside of the impact plate (41) is provided with a counter thrust mechanism (7), the counter thrust mechanism (7) comprises an annular groove (71) formed in the inside of the impact plate (41), a gas jet hole (72) is formed in the surface of the impact plate (41), and a gas conveying groove B (73) is communicated between the conversion groove (43) and the gas jet hole (72). The upper side of the placement table (2) is provided with a cleaning mechanism (8). 2.The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The surface of the impact plate (41) is provided with a scale line, one side of the indicating rod (48) is provided with an indicating needle, and a one-way valve (49) is arranged on the surface of the piston rod (44). 3.The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The bottom end of the sealing plate (46) is provided with a first spring, and the bottom end of the first spring is fixedly connected with the inner wall of the gas conveying groove (42).

4. The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The temperature adjusting assembly comprises a control valve (54) arranged on the outer wall of the cold air pipe (51) and the hot air pipe (52), a valve rod (55) is rotatably arranged on one side of the control valve (54), and a rack (56) engaged with the valve rod (55) is welded on one side of the impact plate (41).

5. The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The gas jet hole (72) is conical, and the diameter of the gas jet hole (72) gradually decreases along the vertical direction of the impact plate (41).

6. The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The cleaning mechanism (8) comprises a spray pipe (81) arranged above the impact plate (41), a telescopic pipe (82) communicated with the outer wall of the spray pipe (81), an installation frame (83) arranged in the inside of the top end of the telescopic pipe (82), a sealing ball (84) slidingly arranged at the opening end of the telescopic pipe (82), a second spring fixedly arranged between the installation frame (83) and the sealing ball (84), a butt joint pipe (85) communicated with the side wall of the mixing pipe (53), and a top rod (86) arranged in the inside of the opening end of the butt joint pipe (85).

7. The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The upper end of the impact plate (41) is provided with a gas collecting cover (74), and the outer side of the impact plate (41) is provided with a rectangular shell (75), and a connecting pipe (76) is communicated between the gas collecting cover (74) and the rectangular shell (75). 8.The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: An electromagnet A (9) is mounted at the output end of the air cylinder (3), and an electromagnet B (10) is mounted at the top end of the impact plate (41) through a support rod.

9. The rock dynamic impact experiment device capable of real-time temperature control according to claim 1, characterized in that: The inner wall of the air jet ring (58) is inclined, and a plurality of exhaust holes are formed in the inner wall of the air jet ring (58), and the air jet ring (58) is communicated with the air supply groove A (59).

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