Weak surrounding rock mechanical drilling device

Abstract

The utility model relates to a weak surrounding rock mechanical drilling device which comprises a drill bit shell, a cutting drill bit is rotatably arranged at one end of the drill bit shell, a power conveying component is rotatably arranged at the other end of the drill bit shell, and the power conveying component is in transmission connection with the cutting drill bit. The cutting drill bit is provided with a hollow channel, an impactor is arranged in the hollow channel, one end of the impactor is provided with an impact drill bit which can extend out of the hollow channel and is used for impacting surrounding rock, and the other end of the impactor extends into the drill bit shell and is in transmission connection with a power transmission component; and a central shaft assembly which extends into the percussion drill bit and is used for stabilizing the percussion drill bit is arranged in the impactor. According to the weak surrounding rock mechanical drilling device, the center shaft assembly is additionally arranged in the inner cavity of the impact cylinder, so that the deviation phenomenon of the impact drill bit in the impact process is corrected, the radial deviation amount of the impact drill bit is reduced, and the service life of the impact drill bit can be effectively prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of highway tunnel construction equipment, in particular to a mechanical drilling device for soft surrounding rocks. Background Art

[0002] Among the surrounding rock grades, Class I: The rock is fresh and complete, the structural influence is slight, the joints and fissures are not developed or slightly developed, closed and not extended for long, there are no or few weak structural surfaces, the fault zone width is <0.1 meters, nearly orthogonal to the tunnel, and the rock mass is in an integral or blocky masonry structure. Class II: The rock is fresh or slightly weathered, and the structural influence is general. The joints and fissures are slightly developed or developed. There are a small number of weak structural surfaces and poor interlayer bonding. The fault fracture zone width is <0.5 meters, oblique or orthogonal to the tunnel, and the rock mass is in a blocky or layered masonry structure. Class III: The rock is slightly weathered or weakly weathered, and the fractures are developed due to the influence of geological structure, and are partially opened and filled with mud. There are many weak structural surfaces, the fault fracture zone is <1 meter, oblique or parallel to the tunnel line, and the rock is in a gravel mosaic structure. Class IV: Same as Class III. There are many fractures and weak structural surfaces, the fault fracture zone is less than 2 meters, parallel to the cave, the rock mass is in a gravel mosaic structure, and locally in a gravel crushed structure. Class V: Loose: Sand layer landslide accumulation and crushed, pebbly, and gravelly soil. Class VI: Loose: Sand layer intercalated with gravel soil and pebble soil, etc.

[0003] In the process of rapid construction of Class III and above surrounding rock by drilling and blasting, tunneling machines are usually selected as construction equipment because there are many weak structures in the surrounding rock, which has higher construction efficiency. Tunneling machines usually include main parts such as the fuselage, cantilever, and mechanical drill installed on the cantilever.

[0004] During the construction process, due to changes in the properties of the surrounding rock, the mechanical drill of the tunnel boring machine may become stuck or even malfunction during the excavation process. The main reason for this phenomenon is that there are also some hard objects mixed in the surrounding rock layer, which makes the low-speed drill bit of the tunnel boring machine unable to cope well. Usually, when encountering such a situation, the equipment will be replaced for targeted drilling and blasting. However, this method takes a long time. The construction tunnel is relatively narrow, and the operation is inconvenient.

[0005] The prior art provides an impact drill bit in the cutting drill bit. When encountering hard rock during the excavation process, the impact drill bit can be used to cut and crush the hard rock, thereby improving the excavation efficiency of the tunnel boring machine, reducing the failure rate of the tunnel boring machine, eliminating the need for additional manual work, and reducing the safety risks of construction.

[0006] In actual use of the prior art, when the impact drill bit driven by high-pressure gas collides with an object, it is easy to produce radial deviation, resulting in a slight shaking of the impact drill bit. The reason is that after the impact drill bit and a large number of irregular hard structures produce reciprocating impacts, the impact force point will be eccentric due to excessive wear of the impact drill bit piston section. Over time, it is easy to reduce the impact force of the impact drill bit and affect the service life of the impact drill bit. Utility Model Content

[0007] The purpose of the utility model is to provide a mechanical drilling device for soft surrounding rock to solve the problems raised in the above-mentioned prior art.

[0008] In order to achieve the above-mentioned purpose of the utility model, the technical solution adopted by the utility model is: a mechanical drilling device for soft surrounding rock, including a drill bit housing, one end of which is rotatably provided with a cutting drill bit, and the other end of which is rotatably provided with a power transmission component, and the power transmission component is transmission-connected with the cutting drill bit;

[0009] The cutting drill bit is provided with a hollow channel, and an impactor is provided in the hollow channel. One end of the impactor is provided with an impact drill bit that can extend out of the hollow channel for impacting the surrounding rock, and the other end of the impactor extends into the drill bit housing and is transmission-connected to the power transmission component;

[0010] The impactor is provided with a central shaft assembly which extends into the impact drill bit and is used to stabilize the impact drill bit.

[0011] Preferably, the impactor includes an impact cylinder with a cavity, and a pneumatic rotary joint mounted outside the impact cylinder, the pneumatic rotary joint includes a rotor fixedly mounted outside the impact cylinder, the rotor is rotatably provided with a stator through a rolling bearing, and a pneumatic conveying cavity is sealed between the rotor and the stator, the stator is provided with a gas conveying port, the rotor is provided with a gas output port, the impact cylinder is provided with a gas inlet connected to the cavity, and the gas output port is connected to a gas inlet pipe.

[0012] Preferably, the impact drill bit is arranged in the inner cavity of the impact cylinder, and the central axis assembly includes a support seat fixedly clamped on the inner cavity wall of the impact cylinder, and a central positioning shaft is inserted on the support seat. The central positioning shaft passes through the side wall of the impact drill bit piston section and extends into the interior.

[0013] Preferably, a stroke cavity is provided in the impact drill bit, and a first positioning block and a second positioning block are provided at both ends of the central positioning shaft, and the second positioning block is placed in the stroke cavity.

[0014] Preferably, the support seat includes a mounting ring seat embedded in the inner cavity wall of the impact cylinder, and the mounting ring seat is provided with support ribs converging toward the middle at intervals. The middle part where the support ribs converge is provided with a through hole passing through along its length direction, and the center positioning shaft is inserted in the through hole.

[0015] Preferably, a tapered hole is provided in the stroke cavity, and a tapered surface is provided on the second positioning block, and the tapered surface is matched with the tapered hole.

[0016] Preferably, the drill housing, the cutting drill bit and the power transmission component are flange-connected via rolling bearings.

[0017] Preferably, the power transmission component comprises a torque limiting coupling connected to the impact cylinder, and a shaft sleeve connected to the torque limiting coupling, and the shaft sleeve is provided with a power input shaft.

[0018] The beneficial effects of the utility model are concentrated in that the soft surrounding rock mechanical drilling device corrects the deviation phenomenon of the impact drill bit during the impact process by adding a central axis component in the inner cavity of the impact cylinder, reduces the radial deviation of the impact drill bit, and can effectively extend the service life of the impact drill bit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an internal schematic diagram of the utility model;

[0020] Figure 2 It is a three-dimensional schematic diagram of the impactor of the utility model;

[0021] Figure 3 This is a front view of the central axis assembly of the utility model;

[0022] Figure 4 It is a side view of the central axis assembly of the utility model;

[0023] Among them, 1. drill bit housing; 2. cutting drill bit; 3. power transmission component; 4. hollow channel; 5. impactor; 6. impact drill bit; 7. center axis assembly; 8. impact cylinder; 9. pneumatic rotary joint; 10. rotor; 11. stator; 12. pneumatic transmission cavity; 13. gas transmission port; 14. gas output port; 15. gas inlet; 16. support seat; 17. center positioning shaft; 18. stroke cavity; 19. first positioning block; 20. second positioning block; 21. mounting ring seat; 22. support rib; 23. through hole; 24. tapered hole; 25. tapered surface; 26. torque limiting coupling; 27. bushing; 28. power input shaft. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below in conjunction with the drawings in the preferred embodiments of the present application.

[0025] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are orientations or positional relationships based on the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0027] In addition, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or display comprising a series of steps or elements is not necessarily limited to those steps or elements explicitly listed, but may include other steps or elements not explicitly listed or inherent to such process, method, product, or display.

[0028] Embodiment 1

[0029] See also Figure 1-Figure 4 A mechanical drilling device for soft surrounding rock, which can be used for rapid drilling and blasting construction of Class III and above surrounding rock. Its construction site can be tunnel construction or highway construction. The mechanical drilling device can be used with a tunnel boring machine to drill and crush soft surrounding rock, and can be its subordinate component.

[0030] In this embodiment, a drill housing 1 is included, one end of which is rotatably provided with a cutting drill bit 2, and the other end of which is rotatably provided with a power transmission component 3, and the power transmission component 3 is transmission-connected to the cutting drill bit 2.

[0031] The power transmission component 3 transmits power to the cutting drill bit 2, and the cutting drill bit 2 rotates to drill and break the surrounding rock. Usually, the cutting drill bit 2 can rotate at a low speed, with a rotation speed of about 0-5r / s, which can meet the requirements of breaking the surrounding rock.

[0032] The drill bit housing 1 can be made of cast steel or carbon steel, which has good strength and toughness and can withstand the pressure and impact force of the cutting drill bit 2 when it is working.

[0033] The cutting drill bit 2 is provided with several sharp teeth for excavation, and the sharp teeth can be made of materials such as cemented carbide, tungsten carbide, artificial diamond and natural diamond. Among them, cemented carbide drill bits have the characteristics of high hardness, good wear resistance and strong impact resistance, and are generally used for drilling rocks with higher hardness. Tungsten carbide drill bits have the advantages of high strength, high hardness and wear resistance, and are suitable for drilling rocks of various hardness. Artificial diamond drill bits and natural diamond drill bits have extremely high hardness and wear resistance, and are suitable for drilling hard and wear-resistant rocks.

[0034] The cutting drill bit 2 is provided with a hollow channel 4, in which an impactor 5 is provided, one end of the impactor 5 is provided with an impact drill bit 6 which can extend out of the hollow channel 4 for impacting the surrounding rock, and the other end of the impactor 5 extends into the drill bit housing 1 and is transmission-connected to the power transmission component 3.

[0035] The hollow channel 4 penetrates the cutting drill bit 2 to provide a space for installing the impactor 5. The impact drill bit 6 is driven by the impactor 5 to achieve rapid impact on a relatively hard object, thereby breaking the relatively hard object.

[0036] Usually, the impact drill bit 6 has a piston section and a working section. The piston section is installed in the impactor 5, and the working section is placed on the outside. The outer surface of the working section can be provided with sharp teeth, which is conducive to crushing objects.

[0037] In order to reduce the impact offset of the impact drill bit 6, the impactor 5 is provided with a central shaft assembly 7 extending into the impact drill bit 6 for stabilizing the impact drill bit 6. The impactor 5 and the central shaft assembly 7 are limited so that the impact drill bit 6 can perform the impact operation more stably and persistently.

[0038] As a more specific implementation of this embodiment, the impactor 5 includes an impact cylinder 8 with a cavity, and a pneumatic rotary joint 9 sleeved outside the impact cylinder 8, the pneumatic rotary joint 9 includes a rotor 10 fixedly sleeved outside the impact cylinder 8, the rotor 10 is provided with a stator 11 through a rolling bearing, and a pneumatic conveying cavity 12 is sealed between the rotor 10 and the stator 11, a gas conveying port 13 is provided on the stator 11, and a gas output port 14 is provided on the rotor 10, and the gas conveying port 13 and the gas output port 14 can be set with holes, and a pipeline connection valve is set at the hole. The pneumatic conveying cavity 12 is set along the annular depression outside the rotor 10, so that the pneumatic conveying cavity 12 and the gas conveying port 13 are still connected during the rotation of the rotor 10, and a group of sealing rings are set between the rotor 10 and the stator 11, and a group of sealing rings are respectively located on both sides of the pneumatic conveying cavity 12 to ensure the air tightness of the pneumatic conveying cavity 12. The sealing ring is made of a material with good wear resistance and can withstand the friction between the rotor 10 and the stator 11 at low speed to ensure air tightness. The impact cylinder 8 is provided with a gas inlet 15 connected to the cavity, and the gas outlet 14 is connected to the gas inlet 15 through a pipeline.

[0039] The impact cylinder 8 is installed in the hollow channel 4 on the cutting drill bit 2. The pneumatic rotary joint 9 allows the gas from the external air pump to enter the impact cylinder 8 while avoiding the entanglement of the pipeline. During operation, the rotor 10 rotates with it, and the stator 11 does not need to rotate. The gas delivery port 13 on the stator 11 is connected to the air pump through a pipeline. The air pump is used to inflate the impact cylinder 8 and form negative pressure, thereby realizing the extension and retraction of the impact drill bit 6. The air pump can deliver high-pressure gas to the impact cylinder 8.

[0040] As a more specific implementation of this embodiment, the impact drill bit 6 is arranged in the inner cavity of the impact cylinder 8, and the central axis assembly 7 includes a support seat 16 fixedly clamped on the inner cavity wall of the impact cylinder 8, and a central positioning shaft 17 is inserted on the support seat 16. The central positioning shaft 17 passes through the side wall of the piston section of the impact drill bit 6 and extends into the interior.

[0041] Specifically, the piston section of the impact drill bit 6 is inserted into the inner cavity of the impact cylinder 8 .

[0042] The support seat 16 should be provided with a vent to provide a passage for the gas coming in from the gas inlet 15 .

[0043] The center positioning shaft 17 is arranged in the middle of the impact cylinder 8, and is aligned with the axis extension line of the impact drill bit 6. The center positioning shaft 17 is arranged to better limit the problem of the impact drill bit 6 deflecting during impact. At the same time, the wall surface of the impact cylinder 8 also limits the position of the impact drill bit 6, and the two achieve the purpose of internal and external positioning.

[0044] A stroke cavity 18 is disposed in the impact drill bit 6 , and a first positioning block 19 and a second positioning block 20 are disposed at both ends of the central positioning shaft 17 , and the second positioning block 20 is placed in the stroke cavity 18 .

[0045] The retractable amount of the second positioning block 20 in the stroke cavity 18 is the impact stroke of the impact drill bit 6. The first positioning block 19 can prevent the central positioning shaft 17 from being separated from the support seat 16, and the second positioning block 20 can prevent the impact drill bit 6 from being separated from the impact cylinder 8. It should be noted that the impact stroke of the impact drill bit 6 does not need to be too long, and the impact speed of the impact drill bit 6 does not need to be too high. It is mainly to provide the impact drill bit 6 with a short-distance propulsion impact force. The propulsion impact force plus the rotational force of the impact drill bit 6 itself is sufficient to break hard objects in Class III and above soft surrounding rocks.

[0046] As a more specific implementation of this embodiment, the support seat 16 includes a mounting ring seat 21 embedded in the inner cavity wall of the impact cylinder 8, and the mounting ring seat 21 is provided with support ribs 22 converging toward the middle at intervals. The middle part where the support ribs 22 converge is provided with a through hole 23 passing through along its length direction, and the center positioning shaft 17 is inserted in the through hole 23.

[0047] The supporting ribs 22 are convex, the force is more uniform, and the supporting performance is better. The center positioning shaft 17 can be pulled by the impact drill 6 to slide in the through hole 23. Of course, in some embodiments, the center positioning shaft 17 can also be fixed on the supporting ribs 22.

[0048] As a more specific implementation of this embodiment, a tapered hole 24 is provided in the stroke cavity 18, and a tapered surface 25 is provided on the second positioning block 20, and the tapered surface 25 is adapted to the tapered hole 24. The tapered surface 25 and the tapered hole 24 are matched and fitted, which can further improve the accuracy of the impact direction of the impact drill bit 6, and more effectively ensure the stability of the impact axis after the equipment is worn.

[0049] As a more specific implementation of this embodiment, the drill housing 1 is flange-connected with the cutting drill bit 2 and the power transmission component 3 through rolling bearings, so that the power transmission component 3 and the cutting drill bit 2 can rotate relative to the drill housing 1. The flange connection is a very conventional technology and will not be described in detail.

[0050] As a more specific implementation of this embodiment, the power transmission component 3 includes a torque limiting coupling 26 connected to the impact cylinder 8, and a sleeve 27 connected to the torque limiting coupling 26, and a power input shaft 28 is provided on the sleeve 27. The torque limiting coupling 26 can solve the problem that the impactor 5 is damaged by excessive torque generated by hard rock cutting when the cutting drill bit 2 rotates. The torque limiting coupling 26 can set a maximum torque. When the torque is greater than the set value during operation, the inner and outer rings of the torque limiting coupling 26 slip to release the torque, thereby protecting the impactor 5.

[0051] The working principle of the mechanical drilling device is roughly as follows: power is transmitted through the power input shaft 28, so that the cutting drill bit 2 rotates to break the surrounding rock. When encountering a relatively hard object, high-pressure gas is injected into the inner cavity of the impact cylinder 8 to push the impact drill bit 6 to impact the hard object in the soft surrounding rock, and the hard object is broken by rotation and impact. During the outward impact of the impact drill bit 6, the central positioning shaft 17 and the impact cylinder 8 limit its travel direction, and the first positioning block 19 and the second positioning block 20 limit its travel distance. During reciprocation, the impact drill bit 6 is retracted by forming a negative pressure in the inner cavity of the impact cylinder 8, and the reciprocating cycle is conducive to the impact drill bit 6 accompanying the cutting drill bit 2 to excavate the surrounding rock.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the description and drawings of the present invention shall be included in the protection scope of the present invention.

Claims

1. A mechanical drilling device for soft surrounding rock, characterized in that: It comprises a drill housing, one end of which is rotatably provided with a cutting drill bit, and the other end of which is rotatably provided with a power transmission component, and the power transmission component is transmission-connected with the cutting drill bit; The cutting drill bit is provided with a hollow channel, and an impactor is provided in the hollow channel. One end of the impactor is provided with an impact drill bit that can extend out of the hollow channel for impacting the surrounding rock, and the other end of the impactor extends into the drill bit housing and is transmission-connected to the power transmission component; The impactor is provided with a central shaft assembly which extends into the impact drill bit and is used to stabilize the impact drill bit.

2. A mechanical drilling device for soft surrounding rock according to claim 1, characterized in that: The impactor includes an impact cylinder with a cavity, and a pneumatic rotary joint sleeved outside the impact cylinder, the pneumatic rotary joint includes a rotor fixedly sleeved outside the impact cylinder, the rotor is rotatably provided with a stator through a rolling bearing, and a pneumatic conveying cavity is sealed between the rotor and the stator, the stator is provided with a gas conveying port, the rotor is provided with a gas output port, the impact cylinder is provided with a gas inlet connected to the cavity, and the gas output port is connected to a gas inlet pipe.

3. A mechanical drilling device for soft surrounding rock according to claim 2, characterized in that: The impact drill bit is arranged in the inner cavity of the impact cylinder, and the central axis assembly includes a support seat fixedly mounted on the inner cavity wall of the impact cylinder, and a central positioning shaft is inserted on the support seat, and the central positioning shaft passes through the side wall of the impact drill bit piston section and extends into the interior; A stroke cavity is arranged in the impact drill bit, and a first positioning block and a second positioning block are arranged at both ends of the central positioning shaft, and the second positioning block is placed in the stroke cavity.

4. A mechanical drilling device for soft surrounding rock according to claim 3, characterized in that: The support seat includes a mounting ring seat embedded in the inner cavity wall of the impact cylinder, and the mounting ring seat is provided with support ribs converging toward the middle at intervals. The middle part where the support ribs converge is provided with a through hole passing through along its length direction, and the center positioning shaft is inserted in the through hole.

5. A mechanical drilling device for soft surrounding rock according to claim 3, characterized in that: A tapered hole is provided in the stroke cavity, and a tapered surface is provided on the second positioning block, and the tapered surface is matched with the tapered hole.

6. A mechanical drilling device for soft surrounding rock according to claim 1, characterized in that: The drill housing, the cutting drill bit and the power transmission component are flange-connected via rolling bearings.

7. A mechanical drilling device for soft surrounding rock according to claim 6, characterized in that: The power transmission component comprises a torque limiting coupling connected to the impact cylinder, and a shaft sleeve connected to the torque limiting coupling, and a power input shaft is arranged on the shaft sleeve.

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