A geological sampling device for limestone mining

Abstract

The present invention relates to the field of mineral mining, and in particular to a geological sampling device for limestone mining; it includes a vehicle body, a driving assembly, a core drill bit, a connecting tube, a grooving block and an extension tube, etc.; the vehicle body is connected to the driving assembly; the driving assembly is connected to the extension tube; the extension tube is detachably connected to the connecting tube; the connecting tube is connected to the core drill bit; the core drill bit is rotatably connected to the grooving block through a torsion spring. The present invention digs a spiral groove on a rock column through the grooving block, and the limiting block I is inserted into the spiral groove on the rock column, so that the rock column cannot continue to fall, thereby avoiding the problem that when drilling to a cavity in the rock layer, the drilled rock column will fall from the drill bit to the bottom of the cavity, which affects the geological sampling.

Description

Technical Field

[0001] The invention relates to the field of mineral mining, in particular to a geological sampling device for limestone mining. Background Art

[0002] In the process of limestone mining, it is necessary to understand the geological structure of the mining area through geological sampling, including the thickness, distribution, interlayer conditions and potential geological disaster risks of the limestone layer, so as to formulate a scientific and reasonable mining plan. In the prior art, a core drill is usually used for geological sampling, which uses a cylindrical drill bit to drill a rock column in the rock layer, and then the rock column is clamped out by a clamping device provided in the drill bit. Then, the staff takes the rock column out of the drill bit to complete the geological sampling. There are usually large and small holes distributed in the rock layer, so that when the drill bit just drills into the hole in the rock layer, the rock column that has not been drilled at the end of the drill bit will fall from the drill bit to the bottom of the hole. When the height of the hole is greater than the height of the drilled rock column, the drilled rock column will fall completely into the hole, making it impossible to take out the rock column, resulting in the need for re-sampling.

[0003] Moreover, due to the hollows in the rock formation, the length of the rock column removed will be shorter than the length required to be removed. Moreover, due to the existence of cracks in the rock formation, the rock column drilled out is not continuous but intermittent, which makes it impossible for the staff to determine where each part of the removed rock column is located in the rock formation, making it difficult for the staff to determine the distribution of the rock formation and the size of the hollows through the sampled rock columns. Summary of the invention

[0004] In order to overcome the disadvantage that when the drill bit drills into a cavity in a rock layer, the drilled rock column will fall from the drill bit to the bottom of the cavity, thus affecting geological sampling, the present invention provides a geological sampling device for limestone mining.

[0005] The technical scheme is as follows: A geological sampling device for limestone mining, including a vehicle body, a driving assembly and an extension tube; the vehicle body is connected to the driving assembly; the driving assembly is connected to the extension tube, and the extension tube is driven to rotate and move up and down through the driving assembly, and the lower end and the upper end of the extension tube are both provided with threads, and the threads at the lower end of the extension tube match the threads at the upper end; it also includes a core drill bit, a connecting tube, a grooving block and a limit block I; the extension tube is detachably connected to the connecting tube, and the connecting tube is provided with threads; the connecting tube is connected to the core drill bit; the core drill bit is rotatably connected to a plurality of grooving blocks through a torsion spring; the connecting tube is rotatably connected to a plurality of limit blocks I through a torsion spring.

[0006] Preferably, the upper end of the limit block I is provided with an inclined surface.

[0007] Preferably, the limit blocks I are arranged in at least two rows.

[0008] Preferably, it further comprises a limiting ring I, and the vehicle body is fixedly connected to the limiting ring I.

[0009] Preferably, a bolt knob II is also included, and the vehicle body is fixedly connected with the bolt knob II.

[0010] Preferably, the lower side of the grooving block is provided with an inclined surface.

[0011] Preferably, it also includes a fixing ring, a limiting ring II, a guide ring, a marking rod, a connecting block and a limiting block II; the connecting tube is fixedly connected to the fixing ring; the fixing ring is fixedly connected to the limiting ring II, and the limiting ring II is provided with a limiting groove, and the limiting ring II is provided with a marking groove, and the limiting groove and the marking groove are staggered; the fixing ring is fixedly connected to the guide ring, and the guide ring is provided with a guide groove, and the positions of the guide groove, the limiting groove and the marking groove correspond to each other; the limiting ring II and the guide ring are slidably connected to the marking rod; the marking rod is rotatably connected to the connecting block; the marking rod is fixedly connected to a spring; and the other end of the spring is fixedly connected to the connecting tube; the marking rod is fixedly connected to a number of limiting blocks II.

[0012] Preferably, the limit block II is set to be trapezoidal.

[0013] Preferably, it also includes a rope and a telescopic rod; the core drill bit is slidably connected to the connecting tube, and a plurality of telescopic rods are fixedly connected between the core drill bit and the connecting tube; the core drill bit is fixedly connected to the rope, and the other end of the rope passes through the connecting tube and is fixedly connected to the connecting block.

[0014] Preferably, a pressure sensor is provided at the lower end of the connecting tube.

[0015] The beneficial effects of the present invention are as follows: the present invention digs a spiral groove on the rock column by means of the groove digging block, and the limiting block I is clamped into the spiral groove on the rock column, so that the rock column cannot continue to fall, thereby avoiding the problem that when drilling to a cavity in the rock formation, the drilled rock column will fall from the drill bit to the bottom of the cavity, thereby affecting geological sampling;

[0016] The present invention leaves marks on the rock column section by section by a marking rod, and the boundary of the marks is the rock stratum cavity, so that the staff can distinguish the distribution of the rock stratum cavities in the rock column by the marks, avoiding the situation that the staff cannot judge the position of each part of the taken rock column in the rock stratum due to the existence of cracks in the rock stratum, making it difficult for the staff to judge the distribution of the rock stratum and the size of the cavity through the sampled rock column.

[0017] The present invention records in detail the time points of compression and reset of the telescopic rod by means of a pressure sensor arranged at the bottom of the connecting tube, so that the staff can calculate the position and size of the cavity in the rock formation by combining the moving speed of the core drill bit with the time of compression and reset of the telescopic rod, so that the staff can determine the position of the mark on each section of the rock column in the rock formation, which is convenient for the staff to judge the geology of the rock formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the structure disclosed by the geological sampling device for limestone mining of the present invention;

[0019] Figure 2 A schematic diagram of the combined structure of a core drill bit and an extension tube disclosed in the geological sampling device for limestone mining of the present invention;

[0020] Figure 3 A cross-sectional view of a core drill bit and a connecting tube disclosed for a geological sampling device for limestone mining of the present invention;

[0021] Figure 4 A cross-sectional view of a retaining ring disclosed for a geological sampling device for limestone mining according to the present invention.

[0022] Explanation of the accompanying drawings: 1-body, 2-core drill bit, 3-connecting cylinder, 4-grooving block, 5-limiting block I, 6-extension cylinder, 101-electric connecting rod, 102-slide rail, 103-slider, 104-fixing plate, 105-tooth ring, 106-bolt knob I, 107-gear, 108-motor, 111-limiting ring I, 112-bolt knob II, 201-fixing ring, 202-limiting ring II, 203-guide ring, 204-marking rod, 205-connecting block, 206-spring, 207-rope, 208-telescopic rod, 20201-limiting groove, 20202-marking groove, 20301-guide groove, 2041-limiting block II. DETAILED DESCRIPTION

[0023] The following descriptions are merely preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention.

[0024] Example 1

[0025] A geological sampling device for limestone mining, such as Figure 1-Figure 4 As shown, it includes a vehicle body 1, an extension tube 6 and a driving assembly; the vehicle body 1 is connected to the driving assembly; the driving assembly is connected to the extension tube 6, and the extension tube 6 is driven to rotate and move up and down by the driving assembly, and the lower end and the upper end of the extension tube 6 are both provided with threads, and the threads at the lower end of the extension tube 6 match the threads at the upper end;

[0026] It also includes a core drill bit 2, a connecting tube 3, a grooving block 4 and a limit block Ⅰ5; the extension tube 6 is detachably connected to the connecting tube 3, and the connecting tube 3 is provided with a thread; the connecting tube 3 is connected to the core drill bit 2; the core drill bit 2 is rotatably connected to eight grooving blocks 4 through a torsion spring, and a spiral groove is left on the rock column through the grooving blocks 4; the connecting tube 3 is rotatably connected to eight limit blocks Ⅰ5 through a torsion spring, and the rock column is limited by the limit blocks Ⅰ5.

[0027] The driving assembly includes an electric connecting rod 101, a slide rail 102, a slider 103, a fixed plate 104, a gear ring 105, a bolt knob Ⅰ106, a gear 107, and a motor 108; the vehicle body 1 is fixedly connected to the electric connecting rod 101; the electric connecting rod 101 is connected to the slide rail 102; the slide rail 102 is slidably connected to the slider 103; the slider 103 is fixedly connected to the fixed plate 104; the fixed plate 104 is rotatably connected to the gear ring 105; the gear ring 105 is fixedly connected to four bolt knobs Ⅰ106; the fixed plate 104 is rotatably connected to the gear 107, and the gear 107 is meshed with the gear ring 105; the slider 103 is bolted to the motor 108, and the output shaft of the motor 108 is fixedly connected to the gear 107.

[0028] The upper end of the limiting block Ⅰ5 is provided with an inclined surface, so that the limiting block Ⅰ5 can be better inserted into the spiral groove on the rock column, thereby better limiting the rock column.

[0029] The limiting blocks Ⅰ5 are arranged in three rows, so that when one row of limiting blocks Ⅰ5 is not inserted into the spiral groove on the rock column, the limiting blocks Ⅰ5 in the remaining two rows can be inserted into the spiral groove.

[0030] It also includes a limiting ring Ⅰ111. The vehicle body 1 is fixedly connected to the limiting ring Ⅰ111. The limiting ring Ⅰ111 is used to limit the core drill bit 2 to prevent the core drill bit 2 from shaking when the core drill bit 2 rotates, thereby preventing the geological sampling from being affected.

[0031] It also includes a bolt knob II 112 , and the vehicle body 1 is fixedly connected with the bolt knob II 112 .

[0032] The lower side of the grooving block 4 is provided with an inclined surface, so that when the grooving block 4 moves downward through the crack on the rock column, the inclined surface of the lower side of the grooving block 4 guides the grooving block 4 to prevent the grooving block 4 from being stuck in the crack on the rock column.

[0033] The working steps of the above embodiment are: first, the staff controls the present invention to move to the rock formation sampling location, and then drives the slide rail 102 to rotate to be perpendicular to the ground through the electric connecting rod 101, and then drives the fixing plate 104 to move downward through the slider 103, and the fixing plate 104 drives the gear ring 105, the bolt knob I 106, the gear 107 and the motor 108 to move downward. Since the bolt knob I 106 is in a close contact state with the extension tube 6 in the initial state, it will also drive the extension tube 6 and all the parts connected to it to move downward. In the process of the core drill bit 2 moving downward, the motor 108 drives the gear 107 to rotate in the counterclockwise direction when viewed from top to bottom. Since the gear 107 is meshed with the gear ring 105, the gear 107 will drive the gear ring 105 and the bolt knob I 106 to rotate in the clockwise direction when viewed from top to bottom, thereby driving the core drill bit 2 and all the parts connected to it to rotate in the clockwise direction when viewed from top to bottom. When the core drill bit 2 moves downward, When it moves to contact the ground, the core drill bit 2 starts to drill downward, thereby drilling a rock column on the rock formation. When the slider 103 moves downward to the lower end of the slide rail 102, the staff rotates the bolt knob I 106 again so that the bolt knob I 106 is no longer in close contact with the core drill bit 2, and then puts the other extension tube 6 together with the extension tube 6 on the core drill bit 2, and fixes the two extension tubes 6 together through the threads at the upper and lower ends of the extension tube 6. Then the slider 103 drives the fixing plate 104 to move upward to the upper end of the upper extension tube 6, and then rotates the bolt knob I 106 again so that the bolt knob I 106 is in close contact with the upper extension tube 6, thereby driving the lower extension tube 6 and the core drill bit 2 to rotate through the upper extension tube 6, and subsequently the extension tube 6 can be continued to be installed on the upper extension tube 6, thereby increasing the length of the extension tube 6 moved downward by the core drill bit 2, so that the core drill bit 2 can continue to drill downward.

[0034] During the rotation of the core drill bit 2, since the clockwise rotation is along the side where the grooving block 4 is in contact with the rock column, the grooving block 4 will not affect the rock column, and the downward movement is along the side where the limit block Ⅰ5 is in contact with the rock column, so the limit block Ⅰ5 will also not affect the rock column; then, when the core drill bit 2 drills downward for a certain distance, the gear 107 is driven to reverse by controlling the motor 108, so that the core drill bit 2 and all the parts connected thereto begin to reverse, so that the grooving block 4 It starts to rotate counterclockwise when viewed from the top, and the counterclockwise rotation is to rotate against the side where the grooving block 4 is in contact with the rock column, so the sharp corner of the grooving block 4 will dig a circle of spiral grooves in the rock column, and then immediately after reversing for a period of time, the motor 108 drives the gear 107 to rotate forward, so that the grooving block 4 starts to rotate forward again, so that the grooving block 4 stops digging grooves on the rock column, so that during the rotation of the core drill bit 2, spiral grooves will be left on the rock column; therefore, when the core drill bit 2 drills to the empty space in the rock formation, When drilling a hole, the rock column loses its support, causing the rock column to fall from the connecting tube 3. When the spiral groove on the rock column falls to the limit block Ⅰ5, since the torsion spring connected between the limit block Ⅰ5 and the connecting tube 3 is in a compressed state, the limit block Ⅰ5 is subjected to the restoring force of the torsion spring and is stuck in the spiral groove on the rock column, so that the rock column cannot continue to fall, thereby avoiding the problem that when drilling to a hole in the rock formation, the drilled rock column will fall from the drill bit to the bottom of the hole, which will affect the geological sampling; subsequently, when the rock is drilled, When the core drill bit 2 drills to the bottom of the rock formation cavity, the core drill bit 2 will contact the rock formation again, thereby continuing to drill out the rock column, and the rock column in the connecting tube 3 moves downward together with the core drill bit 2. When the rock column in the connecting tube 3 of the core drill bit 2 contacts the newly drilled rock column, the rock column in the connecting tube 3 will no longer move downward. After the grooving block 4 continues to move, the grooving block 4 is squeezed by the rock column, so that the grooving block 4 is separated from the spiral groove on the rock column, thereby facilitating the subsequent limiting of the rock column.

[0035] Subsequently, when the core drill 2 drills to the required sampling position, the motor 108 stops rotating, causing the gear 107 to stop rotating, and then the fixed plate 104 and all the connections connected to it are driven to move upward through the slider 103, thereby pulling the core drill 2 upward through the extension tube 6, and when the limit block Ⅰ5 moves upward to the spiral groove of the rock column, the limit block Ⅰ5 will be stuck in the spiral groove on the rock column, so that the extension tube 6 drives the rock column upward through the limit block Ⅰ5, and when the slider 103 moves upward to the upper end of the slide rail 102, at this time, the connection position of the uppermost extension tube 6 and the lower extension tube 6 is above the ground, and the staff turns the bolt knob Ⅱ112 so that the bolt knob Ⅱ112 is tightly attached to the lower extension tube 6, thereby avoiding After the bolt knob Ⅰ106 and the uppermost extension tube 6 are loosened, the lower extension tube 6 and the core drill bit 2 fall down, and then the staff loosens the bolt knob Ⅰ106 and the uppermost extension tube 6, and controls the slider 103 to drive the bolt knob Ⅰ106 to move downward to the upper end of the lower extension tube 6, and then the staff turns the bolt knob Ⅰ106 again to make the bolt knob Ⅰ106 and the lower extension tube 6 fit tightly, and then separates the uppermost extension tube 6 from the lower extension tube 6, and takes out the rock column, and then continues to drive the bolt knob Ⅰ106 and the extension tube 6 to move upward through the slider 103, and repeats this process until the core drill bit 2 moves upward to the ground, and then takes out the rock column in the core drill bit 2, thereby completing the geological sampling.

[0036] Example 2

[0037] On the basis of Example 1, Figure 3 and Figure 4 As shown, it also includes a fixing ring 201, a limiting ring II 202, a guide ring 203, a marking rod 204, a connecting block 205 and a limiting block II 2041; the connecting tube 3 is fixedly connected with the fixing ring 201; the fixing ring 201 is fixedly connected with the limiting ring II 202, and the limiting ring II 202 is provided with a limiting groove 20201, and the limiting ring II 202 is provided with a marking groove 20202, and the limiting groove 20201 and the marking groove 20202 are staggered; the fixing ring 201 is fixedly connected with the guide Guide ring 203, and the guide ring 203 is provided with a guide groove 20301, and the guide groove 20301 corresponds to the position of the limit groove 20201 and the marking groove 20202; the limit ring II 202 and the guide ring 203 are slidably connected with the marking rod 204; the marking rod 204 is rotatably connected with the connecting block 205; the marking rod 204 is fixedly connected with the spring 206; and the other end of the spring 206 is fixedly connected with the connecting tube 3; the marking rod 204 is fixedly connected with four limit blocks II 2041.

[0038] The limit block II 2041 is set to be trapezoidal, so that the limit block II 2041 is guided by the marking groove 20202 and the guide groove 20301.

[0039] It also includes a rope 207 and a telescopic rod 208; the core drill bit 2 is slidably connected to the connecting tube 3, and eight telescopic rods 208 are fixedly connected between the core drill bit 2 and the connecting tube 3; the core drill bit 2 is fixedly connected to the rope 207, and the other end of the rope 207 passes through the connecting tube 3 and is fixedly connected to the connecting block 205.

[0040] A pressure sensor is provided at the lower end of the connecting tube 3 .

[0041] The working steps of the above embodiment are as follows: during the process of the core drill bit 2 drilling the rock formation, since the extension tube 6 is connected to the core of the connecting tube 3, when the core drill bit 2 first contacts the rock formation, the core drill bit 2 is squeezed by the rock formation, causing the core drill bit 2 to pause moving downward, while the core of the connecting tube 3 continues to move downward, causing the core of the connecting tube 3 to move downward in the core drill bit 2, and the telescopic rod 208 is compressed. In the initial state, since the elastic force of the telescopic rod 208 is greater than the elastic force of the spring 206, when the telescopic rod 208 is not compressed, the telescopic rod 208 makes the distance between the core drill bit 2 and the connecting tube 3 larger, thereby pulling the rope 207 in a taut state. , and the spring 206 is in a compressed state; therefore, when the telescopic rod 208 is compressed, the spring 206 resets and pushes the marking rod 204 to move in the direction close to the rock column, so that the marking rod 204 contacts the rock column, and thus, during the downward movement of the marking rod 204, a mark will be left on the rock column; subsequently, when the core drill bit 2 drills into the rock formation cavity, the core drill bit 2 is no longer squeezed by the rock formation, so the telescopic rod 208 will push the core drill bit 2 to move in the direction away from the connecting tube 3, thereby pulling the rope 207 again, and the rope 207 will pull the marking rod 204 and the connecting block 205 to move in the direction away from the rock column, and the spring 206 is compressed again When the limit block II 2041 moves to contact with the guide groove 20301, the limit block II 2041 moves along the guide groove 20301, so that the marking rod 204 rotates; then when the core drill bit 2 drills to the bottom of the rock formation cavity, the core drill bit 2 contacts the rock formation again, so that the telescopic rod 208 is compressed again, and then the spring 206 is reset again to push the marking rod 204 to move in the direction close to the rock column. Since the marking rod 204 rotates under the guidance of the guide groove 20301, when the marking rod 204 moves in the direction close to the rock column, the limit block II 2041 will no longer enter the marking groove 20202, but enter the limit block II 2041. The marking rod 204 is limited in the positioning groove 20201 by the limiting groove 20201, so that the marking rod 204 cannot contact the rock column, and thus the marking rod 204 cannot continue to mark on the rock column; subsequently, when the core drill bit 2 drills to the next rock formation cavity, the marking rod 204 will be pulled by the rope 207 again to move closer to the connecting tube 3, and rotate again under the guidance of the guide ring 203, and then when the core drill bit 2 contacts the rock formation again, the spring 206 will push the marking rod 204 again to move closer to the rock column, so that the marking rod 204 contacts the rock column again, thereby continuing to mark on the rock column, and so on;Thus, when the core drill bit 2 first contacts the rock formation, it will leave a mark on the rock column, and then stop leaving a mark on the rock column after passing through a rock formation cavity, and then continue to mark after passing through the rock formation cavity again, so that a section of marks are left on the rock column, and the boundary of the mark is the rock formation cavity, so that the staff can distinguish the distribution of the rock formation cavities in the rock column through the mark, avoiding the staff being unable to judge where each part of the taken rock column is in the rock formation due to the presence of cracks in the rock formation, making it difficult for the staff to judge the distribution of the rock formation and the size of the cavity through the sampled rock column. ;

[0042] And when the telescopic rod 208 is compressed and reset, the pressure sensor set at the bottom of the connecting tube 3 can be used to record the time points of compression and reset of the telescopic rod 208 in detail, so that the staff can calculate the position and size of the cavity in the rock formation through the movement speed of the core drill bit 2 combined with the time of compression and reset of the telescopic rod 208, so that the staff can determine the position of the mark on each section of the rock column in the rock formation, which is convenient for the staff to judge the geology of the rock formation.

[0043] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A geological sampling device for limestone mining, comprising a vehicle body (1), an extension tube (6) and a drive assembly; the vehicle body (1) is connected to the drive assembly; the drive assembly is connected to the extension tube (6), the extension tube (6) is driven to rotate by the drive assembly, and the extension tube (6) is driven to move up and down, and the lower end and the upper end of the extension tube (6) are both provided with threads, and the threads at the lower end of the extension tube (6) match the threads at the upper end; it is characterized in that It also includes a core drill bit (2), a connecting tube (3), a groove block (4) and a limit block I (5); the extension tube (6) is detachably connected to the connecting tube (3), and the connecting tube (3) is provided with a thread; the connecting tube (3) is connected to the core drill bit (2); the core drill bit (2) is rotatably connected to a plurality of groove blocks (4) via a torsion spring; the connecting tube (3) is rotatably connected to a plurality of limit blocks I (5) via a torsion spring; The invention also comprises a fixing ring (201), a limiting ring II (202), a guide ring (203), a marking rod (204), a connecting block (205) and a limiting block II (2041); the connecting tube (3) is fixedly connected to the fixing ring (201); the fixing ring (201) is fixedly connected to the limiting ring II (202), and the limiting ring II (202) is provided with a limiting groove (20201), and the limiting ring II (202) is provided with a marking groove (20202), and the limiting groove (20201) and the marking groove (20202) are staggered; the fixing ring (201) is fixedly connected to the guide ring (203), and the guide ring (203) is provided with a guide groove (20301), and the guide groove (20301) corresponds to the position of the limit groove (20201) and the marking groove (20202); the limit ring II (202) and the guide ring (203) are slidably connected with a marking rod (204); the marking rod (204) is rotatably connected with a connecting block (205); the marking rod (204) is fixedly connected with a spring (206); and the other end of the spring (206) is fixedly connected with the connecting tube (3); the marking rod (204) is fixedly connected with a plurality of limit blocks II (2041).

2. A geological sampling device for limestone mining according to claim 1, characterized in that: The upper end of the limit block Ⅰ (5) is provided with an inclined surface.

3. A geological sampling device for limestone mining according to claim 1, characterized in that: The limit blocks Ⅰ (5) are arranged in at least two rows.

4. A geological sampling device for limestone mining according to claim 1, characterized in that: It also includes a limiting ring I (111), and the vehicle body (1) is fixedly connected to the limiting ring I (111).

5. A geological sampling device for limestone mining according to any one of claims 1 to 4, characterized in that: It also includes a bolt knob II (112), and the vehicle body (1) is fixedly connected with the bolt knob II (112).

6. A geological sampling device for limestone mining according to claim 5, characterized in that: The lower side surface of the grooving block (4) is provided with an inclined surface.

7. A geological sampling device for limestone mining according to claim 1, characterized in that: The limit block II (2041) is set to be trapezoidal.

8. A geological sampling device for limestone mining according to claim 1, characterized in that: The invention also comprises a rope (207) and a telescopic rod (208); the core drill bit (2) and the connecting tube (3) are slidably connected, and a plurality of telescopic rods (208) are fixedly connected between the core drill bit (2) and the connecting tube (3); the core drill bit (2) is fixedly connected to the rope (207), and the other end of the rope (207) passes through the connecting tube (3) and is fixedly connected to the connecting block (205).

9. A geological sampling device for limestone mining according to claim 8, characterized in that: A pressure sensor is arranged at the lower end of the connecting tube (3).

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