A rock drill pipe automatic tensioning mechanism and a rock drill

Abstract

The utility model discloses a kind of automatic tensioning mechanism of rock drill pipeline and rock drill, belong to rock drilling equipment technical field, the device connects the one end of rock drill pipeline far from rock drilling unit on pipeline partition plate, and moves along the length direction of support by tensioning oil cylinder to push pipeline partition plate, to adjust the pre-tightening amount of rock drill pipeline in this way, tensioning oil cylinder is connected with propelling oil cylinder by oil circuit unit, oil circuit unit is used to introduce hydraulic oil to the rodless chamber of tensioning oil cylinder when the rodless chamber of propelling oil cylinder is oil, and it is used to discharge the hydraulic oil in the rodless chamber of tensioning oil cylinder when the rod chamber of propelling oil cylinder is oil, so that tensioning oil cylinder can drive pipeline partition plate to move to the rear end of support and restore to initial state, to reduce the pre-tightening amount of rock drill oil circuit, so that the pre-tightening amount of rock drill pipeline can quickly restore to initial state, especially drill sticking and pull out drill rod condition, retreat pressure is very big, at this time, it is more necessary to unload the hydraulic oil in the rodless chamber of tensioning oil cylinder through oil circuit unit, avoid causing pipeline damage.

Description

Technical Field

[0001] This utility model relates to the field of rock drilling equipment technology, specifically to an automatic tensioning mechanism for the pipeline of a rock drill and a rock drill. Background Technology

[0002] As a key piece of equipment in tunnel excavation and mining, rock drilling rigs and their pipelines need to be tensioned because the rock drills and their pipelines need to move back and forth frequently during drilling. This is to prevent the pipelines from being worn due to contact with the edges of the propulsion beam structure or falling into the wire reel groove during the reciprocating motion. However, during the drilling process, the rock drill will be subjected to the reaction force during drilling, and the steel wire rope that pulls the rock drill forward will be stretched under the reaction force. At this time, the distance between the rock drill and the rear turntable will decrease, resulting in a reduction in the pre-tightening amount of the rock drill pipeline. In order to avoid the rock drill pipeline from becoming loose during the drilling process, it is necessary to adjust the pre-tightening amount of the rock drill pipeline in real time according to the working status of the rock drill. For example, Chinese invention patent application CN115199819A discloses an automatic adjustment device for the oil pipe of a propulsion beam, including a propulsion cylinder mounted on the propulsion beam, which drives a rock drill to move via a wire rope; a turntable fixedly connected to the propulsion cylinder, which moves synchronously with the propulsion cylinder; a connecting frame mounted on the propulsion beam, on which an oil pipe is installed, with the end of the oil pipe away from the connecting frame passing around the turntable and fixedly connected to the rock drill; a through-plate joint; and an adjustment component used to adjust the tension of the oil pipe during the movement of the rock drill. This invention, by setting the adjustment component, applies an additional pulling force to the oil pipe during the movement of the rock drill, causing the oil pipe to remain taut. The time for applying the pulling force to the oil pipe is shorter, and the effect is better, thereby reducing the probability of permanent deformation of the oil pipe due to the pulling force.

[0003] The aforementioned patent adjusts the tension of the oil pipe by adjusting the position of the adjusting plate joint of the component. However, according to paragraphs 52-26 of its specification, the adjusting mechanism includes a cylinder, a piston rod, a tension spring, and a connecting joint. Furthermore, according to paragraph 57 of its specification, when the rock drill 22 retracts, its retraction speed is slow, the load is small, and no external force acts on the rock drill 22. Therefore, the rock drill 22 and the turntable 12 move relatively synchronously at this time, and the retraction pressure is small. The hydraulic strength of the hydraulic oil in the retraction oil pipe 46 is also low. Therefore, the hydraulic pressure on the piston rod 42 inside the cylinder 4 is relatively low. The tension of the piston rod 42 is reduced under the action of the tension spring 43, which causes the connecting frame 2 to move in the opposite direction. At this time, the pushing force of the connecting frame 2 on the adjusting nut 24 and the plate joint 23 is reduced, which reduces the tension of the oil pipe 21 between the rock drill 22, the turntable 12 and the connecting frame 2, and reduces the probability of the oil pipe 21 being subjected to excessive tension and thus deforming. When the rock drill 22 and the turntable 12 are fully reset, there is no hydraulic pressure in the cylinder 4, and the piston rod 42 is fully reset under the action of the tension spring 43. At this time, the connecting frame 2 will not exert additional pulling force on the oil pipe 21. As described above, the piston rod in the aforementioned patent application resets via a tension spring at its end furthest from the plate joint. The tension spring's elasticity resists the oil pressure during the retraction of the propulsion cylinder. However, in actual rock drill operation, the retraction pressure of the propulsion cylinder is higher than its forward pressure during rapid retraction reset and drill bit removal. Since the rock drill pipeline tensioning primarily compensates for the elongation of the forward wire rope during drilling, if the solution described in the patent application is adopted, the tension spring's elasticity is insufficient to push the piston rod to reset during rapid retraction reset and drill bit removal. This results in the pre-tension of the rock drill pipeline being significantly higher than the preset pre-tension under these conditions, potentially causing permanent pipeline deformation and accelerated wear. Based on this, the present invention designs an automatic tensioning mechanism for the pipeline of a rock drill and a rock drill to solve the above problems. Utility Model Content

[0004] This utility model provides an automatic tensioning mechanism for the pipeline of a rock drill and a rock drill, to solve the technical problem in the prior art of introducing the forward and backward pressures of the propulsion cylinder to the same side of the piston column.

[0005] According to one aspect of this utility model, an automatic tensioning mechanism for a rock drill pipeline is provided, used to adjust the tension of the rock drill pipeline connected to the rear end of the rock drill unit, which is mounted on the rock drill. The rock drill further includes a support, a propulsion cylinder, and a wire rope. The rock drill unit is slidably mounted on the support along its length and is used for drilling. The propulsion cylinder is used to drive the rock drill unit to move on the support via the wire rope. The automatic tensioning mechanism for the rock drill pipeline includes a tensioning cylinder, a pipeline partition, and an oil circuit unit. The pipeline partition is slidably mounted on the support along the length of the support. The pipeline partition is also used to connect to the end of the rock drill pipeline away from the rock drilling unit. The tensioning cylinder is fixed on the support and used to drive the pipeline partition to slide along the length of the support. The hydraulic circuit unit is used to connect the propulsion cylinder and the tensioning cylinder. The hydraulic circuit unit is used to introduce hydraulic oil into the rodless chamber of the tensioning cylinder when oil is introduced into the rodless chamber of the propulsion cylinder, and to discharge the hydraulic oil in the rodless chamber of the tensioning cylinder when oil is introduced into the rod chamber of the propulsion cylinder.

[0006] As a further embodiment of this utility model, the tensioning cylinder is a plunger cylinder, and the oil circuit unit includes a first branch, a second branch, a third branch, and a reversing valve. The first branch connects the rodless chamber of the propulsion cylinder to the first end of the reversing valve. The second branch connects the second end of the reversing valve to the oil tank. The third branch connects the third end of the reversing valve to the rodless chamber of the tensioning cylinder. The reversing valve is used to switchably conduct its third end relative to either the first or second end.

[0007] As a further embodiment of this utility model, the tensioning cylinder is a double-acting cylinder, and the oil circuit unit includes a fourth branch, a fifth branch, a sixth branch, a seventh branch, and a reversing valve. The fourth branch connects the rodless chamber of the propulsion cylinder to the first end of the reversing valve. The fifth branch connects the return oil circuit to the second end of the reversing valve. The sixth branch connects the rodless chamber of the tensioning cylinder to the third end of the reversing valve. The seventh branch connects the rod chamber of the tensioning cylinder to the fourth end of the reversing valve. The reversing valve is used to switch between a first working state and a second working state. In the first working state, its first end is connected to the third end, and its second end is connected to the fourth end. In the second working state, its first end is connected to the fourth end, and its second end is connected to the third end.

[0008] As a further embodiment of this utility model, the reversing valve is a hydraulically controlled reversing valve, and the driving end of the reversing valve is connected to the rod chamber of the propulsion cylinder through a pipeline.

[0009] As a further embodiment of this utility model, the tensioning cylinder is a double-acting cylinder, and the oil circuit unit includes an eighth branch and a ninth branch. The eighth branch connects the rodless chamber of the propulsion cylinder and the rodless chamber of the tensioning cylinder, and the ninth branch connects the rod chamber of the propulsion cylinder and the rod chamber of the tensioning cylinder.

[0010] As a further embodiment of this invention, the ratio of the cylinder diameter to the rod diameter of the tensioning cylinder is greater than the ratio of the cylinder diameter to the rod diameter of the propulsion cylinder.

[0011] As a further embodiment of this invention, the maximum stroke of the tensioning cylinder is used to match the tension of the wire rope.

[0012] As a further embodiment of this utility model, a base is fixedly mounted on the bracket, a slide rail is provided on the base, the pipeline partition is slidably mounted on the slide rail, the tensioning cylinder is fixedly mounted on the base, and the piston rod of the tensioning cylinder is fixedly connected to the pipeline partition.

[0013] As a further embodiment of this utility model, a pipe joint is provided through the pipe partition plate. The pipe joint is used to connect the end of the rock drill pipe away from the rock drilling unit. An adjusting nut is threaded on the pipe joint. The adjusting nut is used to abut against the pipe partition plate and to adjust and fix the position of the pipe joint on the pipe partition plate.

[0014] A rock drill includes the aforementioned automatic tensioning mechanism for the rock drill pipeline.

[0015] This utility model has the following beneficial effects: This device connects the end of the rock drill pipeline furthest from the drilling unit to a pipeline partition. A tensioning cylinder moves the partition along the length of the support to adjust the preload of the rock drill pipeline. The tensioning cylinder is connected to the propulsion cylinder via a hydraulic circuit unit. This unit introduces hydraulic oil into the rodless chamber of the tensioning cylinder when the propulsion cylinder's rodless chamber is filled, and discharges hydraulic oil from the rodless chamber of the tensioning cylinder when the propulsion cylinder's rod chamber is filled. This allows the tensioning cylinder to move the pipeline partition towards the rear of the support and return it to its initial state, reducing the preload of the rock drill pipeline and enabling it to quickly return to its initial state. This is especially important during stuck drill and drill bit removal operations, where the backward pressure is very high. In such cases, it is necessary to discharge the hydraulic oil from the rodless chamber of the tensioning cylinder through the hydraulic circuit unit to prevent pipeline damage.

[0016] In addition to the objectives, features, and advantages described above, this utility model has other objectives, features, and advantages. The present utility model will now be described in further detail with reference to the figures. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings: Figure 1 This is a top view of the overall structure of this utility model; Figure 2 This is a side view of the overall structure of this utility model; Figure 3 This is the first example schematic diagram of an oil circuit unit; Figure 4 This is a second example schematic diagram of an oil circuit unit; Figure 5 This is the third example schematic diagram of an oil circuit unit; Figure 6 This is a schematic diagram of the installation of the pipeline partition in this utility model.

[0018] Legend: 1. Rock drilling unit; 2. Rock drill piping; 3. Support frame; 4. Propulsion cylinder; 5. Wire rope; 6. Tensioning cylinder; 7. Pipeline partition; 8. First branch; 9. Second branch; 10. Third branch; 11. Reversing valve; 12. Fourth branch; 13. Fifth branch; 14. Sixth branch; 15. Seventh branch; 16. Ninth branch; 17. Base; 18. Slide rail; 19. Pipeline connector; 20. Adjusting nut; 21. Pulley; 22. Cylinder connecting seat; 23. Piston column connecting seat; 24. Eighth branch. Detailed Implementation

[0019] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0020] Please see Figure 1-6 The present invention provides a technical solution: a rock drill pipe 2 connected to the rear end of the rock drill unit 1 is installed on the rock drill to adjust the tension of the pipe. The rock drill also includes a support 3, a propulsion cylinder 4 and a wire rope 5. The rock drill unit 1 is slidably installed on the support 3 along the length of the support 3 and is used for drilling. The propulsion cylinder 4 is used to drive the rock drill unit 1 to move on the support 3 through the wire rope 5. Specifically, two pulleys 21 are slidably installed on the support 3 along its length. One of the pulleys 21 is located in front of the rock drilling unit 1, and the other pulley 21 is located behind the rock drilling unit 1. The front end of the rock drilling unit 1 is connected to a forward steel wire rope 5, and the rear end of the rock drilling unit 1 is connected to a backward steel wire rope 5. The forward steel wire rope 5 passes around the pulley 21 at the front end of the rock drilling unit 1 and is fixed on the support 3. The backward steel wire rope 5 passes around the pulley 21 at the rear end of the rock drilling unit 1 and is fixed in the middle of the support 3. The propulsion cylinder 4 drives the two pulleys 21 to move synchronously, thereby realizing the forward or backward movement of the rock drilling unit 1 on the support 3. The stroke of the propulsion cylinder 4 is amplified by the cooperation of the steel wire rope 5 and the pulleys 21. The automatic tensioning mechanism for the rock drill pipeline includes a tensioning cylinder 6, a pipeline partition 7, and an oil circuit unit. The pipeline partition 7 is slidably mounted on the support 3 along the length of the support 3. The pipeline partition 7 is also used to connect to the end of the rock drill pipeline 2 away from the rock drilling unit 1. The tensioning cylinder 6 is fixed on the support 3 and is used to drive the pipeline partition 7 to slide along the length of the support 3. The oil circuit unit is used to connect the push cylinder 4 and the tensioning cylinder 6. The oil circuit unit is used to introduce hydraulic oil into the rodless chamber of the tensioning cylinder 6 when oil is introduced into the rodless chamber of the push cylinder 4, and to discharge the hydraulic oil in the rodless chamber of the tensioning cylinder 6 when oil is introduced into the rod chamber of the push cylinder 4. One end of the rock drill pipe 2 is fixed to the rear end of the rock drill unit, and the other end passes around the pulley 21 at the rear end of the rock drill unit 1 and is fixed to the pipe partition 7. During operation, oil enters the rodless chamber of the propulsion cylinder 4 and exits from the rod chamber. Simultaneously, the propulsion cylinder 4 drives two pulleys 21 to move towards the front end of the support 3. The pulley 21 in front of the drilling unit 1 moves the drilling unit 1 forward via the forward steel wire rope 5. When the drilling unit 1 is drilling, the reaction force acts on the forward steel wire rope 5, causing it to stretch. This reduces the distance between the drilling unit 1 and the pulley 21 at its rear end, thus reducing the preload of the rock drill pipe 2 connected to the drilling unit 1. Meanwhile, the hydraulic system connects the propulsion cylinder 4 to the tensioning cylinder 6. When oil enters the rodless chamber of the propulsion cylinder 4, the hydraulic system introduces pressurized hydraulic oil into the rodless chamber of the tensioning cylinder 6. The tensioning cylinder 6 then extends, pushing the pipe partition 7 towards the front end of the support 3, increasing the preload of the rock drill pipe 2 and thus offsetting the reduction in preload during drilling. To prevent loosening of the rock drill pipe 2 and extend its service life, when the rock drill unit 1 needs to be retracted, oil is introduced into the rod chamber of the push cylinder 4 and discharged from the rodless chamber. The push cylinder 4 drives the two pulleys 21 to move synchronously towards the rear end of the support 3. At this time, the forward wire rope 5 is no longer subjected to reaction force and returns to its initial length. To avoid excessive pre-tension of the rock drill pipe 2, when oil is introduced into the rod chamber of the push cylinder 4, the hydraulic circuit unit will discharge the hydraulic oil in the rodless chamber of the tension cylinder 6. This allows the tension cylinder 6 to drive the pipe partition 7 to move towards the rear end of the support 3 and return to its initial state, thereby reducing the pre-tension of the rock drill hydraulic circuit. This allows the pre-tension of the rock drill pipe 2 to quickly return to its initial state, especially in the case of stuck drill and drill bit removal, where the retraction pressure is very high. In this case, it is even more necessary to discharge the hydraulic oil in the rodless chamber of the tension cylinder 6 through the hydraulic circuit unit to avoid damage to the pipe.

[0021] Specifically, when the tensioning cylinder 6 is a plunger cylinder, the oil circuit unit includes a first branch 8, a second branch 9, a third branch 10, and a reversing valve 11. The first branch 8 connects the rodless chamber of the propulsion cylinder 4 to the first end of the reversing valve 11. The second branch 9 connects the second end of the reversing valve 11 to the oil tank. The third branch 10 connects the third end of the reversing valve 11 to the rodless chamber of the tensioning cylinder 6. The reversing valve 11 is used to switch its third end relative to the first end or the second end. Figure 3 The first example of a hydraulic circuit unit is disclosed. In this example, the tensioning cylinder 6 is a plunger cylinder. The hydraulic circuit unit includes a first branch 8, a second branch 9, a third branch 10, and a reversing valve 11. The first branch 8 connects the rodless chamber of the push cylinder 4 to the first end of the reversing valve 11. The second branch 9 connects the second end of the reversing valve 11 to the oil tank. The third branch 10 connects the third end of the reversing valve 11 to the rodless chamber of the tensioning cylinder 6. The reversing valve 11 is used to switch its third end relative to the first and second ends. When oil enters the rodless chamber of the push cylinder 4, the first and third ends of the reversing valve 11 are connected. The first branch 8 introduces pressurized hydraulic oil into the rodless chamber of the tensioning cylinder 6. At this time, the piston rod of the tensioning cylinder 6 extends and pushes the pipeline partition 7 to move towards the front end of the bracket 3, thereby increasing the preload of the rock drill pipeline 2 and preventing the rock drill pipeline 2 from being overloaded. When the rock drilling unit 1 retracts, the reversing valve 11 connects its second end to its third end. The rodless chamber of the tensioning cylinder 6 is connected to the oil tank through the third branch 10 and the second branch 9. At this time, under the action of the tensioning force of the rock drill pipeline 2, the pipeline partition 7 can be driven to move towards the rear end of the support 3, thereby causing the piston rod of the tensioning cylinder 6 to retract. The hydraulic oil in the rodless chamber of the tensioning cylinder 6 can be directly discharged into the oil tank through the third branch 10 and the second branch 9, realizing the emptying of the hydraulic oil in the rodless chamber of the tensioning cylinder 6, so that the tensioning cylinder 6 returns to its initial state. Similarly, the tensioning cylinder 6 will drive the pipeline partition 7 to return to its initial state, and finally restore the pre-tightening amount of the rock drill pipeline 2 to the preset state. In the case of the rock drilling unit 1 retracting and the drill bit being stuck and pulled out, the pre-tightening amount of the rock drill pipeline 2 can be avoided to be too large, and the rock drill pipeline 2 can be avoided to be damaged. Specifically, the tensioning cylinder 6 is a double-acting cylinder. The oil circuit unit includes a fourth branch 12, a fifth branch 13, a sixth branch 14, a seventh branch 15, and a reversing valve 11. The fourth branch 12 connects the rodless chamber of the propulsion cylinder 4 to the first end of the reversing valve 11. The fifth branch 13 connects the return oil circuit to the second end of the reversing valve 11. The sixth branch 14 connects the rodless chamber of the tensioning cylinder 6 to the third end of the reversing valve 11. The seventh branch 15 connects the rod chamber of the tensioning cylinder 6 to the fourth end of the reversing valve 11. The reversing valve 11 is used to switch between a first working state and a second working state. In the first working state, its first end is connected to the third end and its second end is connected to the fourth end. In the second working state, its first end is connected to the fourth end and its second end is connected to the third end. Figure 4 A second example of the hydraulic circuit unit is disclosed. In this example, the tensioning cylinder 6 is a double-acting cylinder. The hydraulic circuit unit includes a fourth branch 12, a fifth branch 13, a sixth branch 14, a seventh branch 15, and a reversing valve 11. The fourth branch 12 connects the rodless chamber of the propulsion cylinder 4 to the first end of the reversing valve 11. The fifth branch 13 connects the return oil circuit to the second end of the reversing valve 11. The sixth branch 14 connects the rodless chamber of the tensioning cylinder 6 to the third end of the reversing valve 11. The seventh branch 15 connects the rod chamber of the tensioning cylinder 6 to the fourth end of the reversing valve 11. The reversing valve 11 is used to open its third end relative to the first or second end, and to open its fourth end relative to the first or second end. In this example, when oil enters the rodless chamber of the propulsion cylinder 4, the reversing valve 11 connects its first end relative to its third end and its second end relative to its fourth end. Pressurized hydraulic oil is then introduced into the rodless chamber of the tensioning cylinder 6 via the fourth branch 12 and the sixth branch 14, causing the piston rod of the tensioning cylinder 6 to extend. Meanwhile, the hydraulic oil in the rod chamber of the tensioning cylinder 6 is introduced into the return oil circuit via the seventh branch 15 and the fifth branch 13, achieving the return of hydraulic oil from the rod chamber of the tensioning cylinder 6. When the propulsion cylinder 4 pushes the drilling unit 1 forward for drilling, the tensioning cylinder 6 also pushes the pipe partition 7 towards the front end of the support 3, increasing the preload of the rock drill pipe 2 and preventing loosening of the rock drill pipe 2. When the rock drill unit 1 retracts, the reversing valve 11... The valve 11 connects its first end to the fourth end and its second end to the third end. At this time, the rodless chamber of the tensioning cylinder 6 is connected to the return oil circuit through the fifth branch 13 and the sixth branch 14, and the rod chamber of the tensioning cylinder 6 is connected to the rodless chamber of the propulsion cylinder 4 through the fourth branch 12 and the seventh branch 15. Since the rodless chamber of the propulsion cylinder 4 is in the return oil state at this time, the rodless chamber and the rod chamber of the tensioning cylinder 6 are connected to the return oil circuit at the same time, so that the oil pressure in the rod chamber and the rodless chamber of the tensioning cylinder 6 is the same. At this time, under the action of the tensioning force of the rock drill pipeline 2, the tensioning cylinder 6 will retract to the initial state, so that the preload of the rock drill pipeline 2 is restored to the initial state, and the preload of the rock drill pipeline 2 is not too large when the rock drill unit 1 retracts. Preferably, in the two examples above, the directional valve 11 is a hydraulically controlled directional valve. The hydraulic port of the hydraulic directional valve 11 is connected to the rod chamber of the propulsion cylinder 4 through a pipeline. The directional valve 11 is switched by the retraction pressure of the propulsion cylinder 4, so that the directional valve 11 switches from the left position to the right position. After the retraction pressure disappears, the directional valve 11 will return from the right position to the left position. In this way, the different working states of the directional valve 11 can be switched when the propulsion cylinder 4 extends and retracts. There is no need to control the directional valve 11 through an additional control unit, making the overall device simpler. like Figure 3As shown, in the first example of the hydraulic circuit unit, the left position of the directional valve 11 is that its first and third ends are open, while the right position of the directional valve 11 is that its second and third ends are open. When the hydraulic oil enters the rod chamber of the propulsion cylinder 4 and causes the propulsion cylinder 4 to retract, the pressurized hydraulic oil will enter the hydraulic control port of the directional valve 11, thereby realizing the switching of the directional valve 11 from the left position to the right position. like Figure 4 As shown, in the second example of the hydraulic circuit unit, the left position of the directional valve 11 is such that its first end is connected to its third end and its second end is connected to its fourth end. The right position of the directional valve 11 is such that its first end is connected to its fourth end and its second end is connected to its third end. When hydraulic oil enters the rod chamber of the propulsion cylinder 4 and causes the propulsion cylinder 4 to retract, the pressurized hydraulic oil will enter the hydraulic control port of the directional valve 11, thereby realizing the switching of the directional valve 11 from the left position to the right position. Specifically, the tensioning cylinder 6 is a double-acting cylinder, and the oil circuit unit includes an eighth branch 24 and a ninth branch 16. The eighth branch 24 connects the rodless chamber of the propulsion cylinder 4 and the rodless chamber of the tensioning cylinder 6, and the ninth branch 16 connects the rod chamber of the propulsion cylinder 4 and the rod chamber of the tensioning cylinder 6. Figure 5 A third example of the hydraulic circuit unit is disclosed. In this example, the tensioning cylinder 6 is a double-acting cylinder. The hydraulic circuit unit includes an eighth branch 24 and a ninth branch 16. The eighth branch 24 connects the rodless chamber of the propulsion cylinder 4 and the rodless chamber of the tensioning cylinder 6. The ninth branch 16 connects the rod chamber of the propulsion cylinder 4 and the rod chamber of the tensioning cylinder 6. The rod chamber of the tensioning cylinder 6 is directly connected to the rod chamber of the propulsion cylinder 4, and the rodless chamber of the tensioning cylinder 6 is directly connected to the propulsion cylinder 4. The rodless chamber allows the tensioning cylinder 6 and the propulsion cylinder 4 to maintain synchronous operation. When oil enters the rodless chamber of the propulsion cylinder 4, oil also enters the rodless chamber of the tensioning cylinder 6. When oil enters the rod chamber of the propulsion cylinder 4, oil also enters the rod chamber of the tensioning cylinder 6. This ensures that the tensioning cylinder 6 always maintains synchronous operation with the propulsion cylinder 4, thereby increasing the preload of the rock drill pipe 2 when the propulsion cylinder 4 extends and decreasing the preload of the rock drill pipe 2 when the propulsion cylinder 4 retracts. Preferably, in the third example of the hydraulic circuit unit, the ratio of the cylinder diameter to the rod diameter of the tensioning cylinder 6 is greater than the ratio of the cylinder diameter to the rod diameter of the propulsion cylinder 4. When the retraction oil pressure can drive the propulsion cylinder 4 to retract, then the current retraction oil pressure can necessarily drive the tensioning cylinder 6 to retract, ensuring that the tensioning cylinder 6 can retract synchronously when the propulsion cylinder 4 retracts, so that the preload of the rock drill pipeline 2 is restored to its initial state.

[0022] Preferably, the maximum stroke of the tensioning cylinder 6 is matched with the tension of the wire rope 5 to ensure that the preload of the rock drill pipe 2 is close to the initial preload during drilling, thereby avoiding excessive differences in preload under different working conditions and improving the service life of the rock drill pipe 2.

[0023] Specifically, a base 17 is fixedly installed on the bracket 3, a slide rail 18 is provided on the base 17, a pipe partition 7 is slidably installed on the slide rail 18, a tensioning cylinder 6 is fixedly installed on the base 17, and the piston rod of the tensioning cylinder 6 is fixedly connected to the pipe partition 7. like Figure 6 As shown, a base 17 is fixedly mounted on the bracket 3, and a slide rail 18 is fixedly mounted on the base 17. The pipe partition 7 is slidably mounted on the slide rail 18 to achieve a sliding fit between the pipe partition 7 and the bracket 3. A cylinder connecting seat 22 is fixedly mounted on the base 17, and the cylinder of the tensioning cylinder 6 is fixedly connected to the cylinder connecting seat 22. A piston rod connecting seat 23 is fixedly mounted on the pipe partition 7, and the piston rod of the tensioning cylinder 6 is fixedly mounted on the piston rod connecting seat 23. The axial direction of the tensioning cylinder 6 is parallel to the length direction of the bracket 3, and the pipe partition 7 can be moved along the length direction of the bracket 3 by the tensioning cylinder 6. Specifically, a pipe connector 19 is provided on the pipe partition 7. The pipe connector 19 is used to connect the end of the rock drill pipe 2 away from the rock drilling unit 1. An adjusting nut 20 is threaded on the pipe connector 19. The adjusting nut 20 is used to abut against the pipe partition 7 and to adjust and fix the position of the pipe connector 19 on the pipe partition 7. like Figure 6 As shown, a pipe connector 19 is installed on the pipe partition 7, and the rock drill pipe 2 is fixed on the pipe connector 19. The pipe connector 19 is fixed on the pipe partition 7 by adjusting nuts 20. Specifically, the pipe connector 19 is threaded with adjusting nuts 20. There are at least two adjusting nuts 20 on the pipe connector 19. The two adjusting nuts 20 are located on the front and rear sides of the pipe partition 7 respectively, and can abut against the front and rear end faces of the pipe partition 7 to fix the pipe connector 19 on the pipe partition 7. At the same time, by adjusting the position of the two adjusting nuts 20 on the pipe connector 19, the position of the pipe connector 19 on the pipe partition 7 can be adjusted, thereby adjusting the initial preload of the rock drill pipe 2.

[0024] A rock drill includes the aforementioned automatic tensioning mechanism for the rock drill pipeline. By adopting the aforementioned automatic tensioning mechanism for the rock drill pipeline, excessive pre-tensioning of the rock drill pipeline 2 can be avoided during retraction or drill jamming and drill bit pulling operations. This can effectively reduce problems such as permanent deformation of the rock drill pipeline 2, damage to the internal steel wire protective layer, and pipe bursting, and can effectively extend the service life of the rock drill pipeline 2.

[0025] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. An automatic tensioning mechanism for a rock drill pipeline, used to adjust the tension of a rock drill pipeline (2) connected to the rear end of a rock drill unit (1) on a rock drill, the rock drill further comprising a support (3), a propulsion cylinder (4), and a wire rope (5), the rock drill unit (1) being slidably mounted on the support (3) along the length of the support (3) and used for drilling, the propulsion cylinder (4) being used to drive the rock drill unit (1) to move on the support (3) via the wire rope (5), characterized in that: The automatic tensioning mechanism of the rock drill pipeline includes a tensioning cylinder (6), a pipeline partition (7), and an oil circuit unit. The pipeline partition (7) is used to slide on the support (3) along the length direction of the support (3). The pipeline partition (7) is also used to connect to the end of the rock drill pipeline (2) away from the rock drilling unit (1). The tensioning cylinder (6) is used to be fixed on the support (3) and to drive the pipeline partition (7) to slide along the length direction of the support (3). The oil circuit unit is used to connect the propulsion cylinder (4) and the tensioning cylinder (6). The oil circuit unit is used to introduce hydraulic oil into the rodless chamber of the tensioning cylinder (6) when oil is introduced into the rodless chamber of the propulsion cylinder (4), and to discharge the hydraulic oil in the rodless chamber of the tensioning cylinder (6) when oil is introduced into the rod chamber of the propulsion cylinder (4).

2. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: The tensioning cylinder (6) is a plunger cylinder. The oil circuit unit includes a first branch (8), a second branch (9), a third branch (10), and a reversing valve (11). The first branch (8) connects the rodless chamber of the propulsion cylinder (4) and the first end of the reversing valve (11). The second branch (9) connects the second end of the reversing valve (11) and the oil tank. The third branch (10) connects the third end of the reversing valve (11) and the rodless chamber of the tensioning cylinder (6). The reversing valve (11) is used to switch its third end relative to the first end or the second end.

3. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: The tensioning cylinder (6) is a double-acting cylinder. The hydraulic circuit unit includes a fourth branch (12), a fifth branch (13), a sixth branch (14), a seventh branch (15), and a reversing valve (11). The fourth branch (12) connects the rodless chamber of the propulsion cylinder (4) to the first end of the reversing valve (11). The fifth branch (13) connects the return oil circuit to the second end of the reversing valve (11). The sixth branch (14) connects the rodless chamber of the tensioning cylinder (6) to the reversing valve (11). The third end of 11), the seventh branch (15) is connected to the rod chamber of the tensioning cylinder (6) and the fourth end of the reversing valve (11). The reversing valve (11) is used to switch between the first working state and the second working state. In the first working state, the first end of the reversing valve (11) is connected to the third end and the second end of the reversing valve (11) is connected to the fourth end. In the second working state, the first end of the reversing valve (11) is connected to the fourth end and the second end of the reversing valve (11) is connected to the third end.

4. An automatic tensioning mechanism for a rock drill pipeline according to claim 2 or 3, characterized in that: The reversing valve (11) is a hydraulically controlled reversing valve, and the driving end of the reversing valve (11) is connected to the rod chamber of the propulsion cylinder (4) through a pipeline.

5. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: The tensioning cylinder (6) is a double-acting cylinder. The oil circuit unit includes an eighth branch (24) and a ninth branch (16). The eighth branch (24) connects the rodless chamber of the propulsion cylinder (4) and the rodless chamber of the tensioning cylinder (6). The ninth branch (16) connects the rod chamber of the propulsion cylinder (4) and the rod chamber of the tensioning cylinder (6).

6. The automatic tensioning mechanism for a rock drill pipeline according to claim 5, characterized in that: The ratio of the cylinder diameter to the rod diameter of the tensioning cylinder (6) is greater than the ratio of the cylinder diameter to the rod diameter of the propulsion cylinder (4).

7. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: The maximum stroke of the tensioning cylinder (6) is used to match the tension of the wire rope (5).

8. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: A base (17) is fixedly installed on the bracket (3), and a slide rail (18) is provided on the base (17). The pipeline partition (7) is slidably installed on the slide rail (18), and the tensioning cylinder (6) is fixedly installed on the base (17). The piston rod of the tensioning cylinder (6) is fixedly connected to the pipeline partition (7).

9. The automatic tensioning mechanism for a rock drill pipeline according to claim 1, characterized in that: Pipe joint (19) is provided on the pipe partition (7). The pipe joint (19) is used to connect the end of the rock drill pipe (2) away from the rock drilling unit (1). An adjusting nut (20) is threaded on the pipe joint (19). The adjusting nut (20) is used to abut against the pipe partition (7) and to adjust and fix the position of the pipe joint (19) on the pipe partition (7).

10. A rock drill, characterized in that: The invention includes an automatic tensioning mechanism for a rock drill pipeline as described in any one of claims 1-9.

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