Powerhead apparatus and drilling apparatus

Abstract

The application discloses a power head device and a drilling equipment, and relates to the technical field of geological equipment. The driving mechanism of the power head device is used for driving the rotation of a main shaft. A vibration exciting executive member is slidably sleeved on the main shaft along the axial direction of the main shaft and can rotate synchronously with the main shaft. The vibration exciting executive member is used for connecting a drilling tool. A first energy storage reset member is used for applying an elastic force to the vibration exciting executive member towards a hole bottom. The vibration exciting executive member is configured to compress the first energy storage reset member when the drilling tool is subjected to rock resistance. A vibration exciting transmission member is used for converting the vibration of the vibration exciting transmission member into the vibration impact movement of the vibration exciting executive member along the axial direction of the main shaft when the compression stroke of the first energy storage reset member reaches a set threshold value, so as to transmit the axial vibration impact to the drilling tool. The drilling equipment comprises a machine body, a drilling tool and the power head device. The application has the advantages of simple structure, low cost and reduced unnecessary energy loss.

Description

Technical Field

[0001] This invention relates to the field of geological equipment technology, and in particular to a power head device and drilling equipment. Background Technology

[0002] The power head unit is the core actuator of drilling equipment. Its function is to drive the drill string system to rotate and transmit the applied pressure to the drill bit at the bottom of the hole to achieve rotary drilling. Existing conventional power heads only have a simple rotary drive function.

[0003] During actual drilling, when the drill string traverses hard strata, encounters rock cuttings accumulation at the bottom of the hole, or experiences borehole narrowing or collapse, the rotational resistance of the drill string increases dramatically, resulting in an "increased drilling torque." If this resistance continues to accumulate, the drill string may become stuck in the borehole wall or rock cuttings, leading to a "stuck drill" accident. To overcome these challenges, conventional power heads can only rely on increasing output torque to force the drill string to move. However, this "hard rotation" method is not only extremely energy-intensive, but also prone to causing drill pipe breakage, motor overload and burnout, and even serious borehole accidents such as drill bit burial when the resistance exceeds limits, posing significant safety hazards.

[0004] Currently, while some power heads on the market possess impact capabilities, their impact actions largely rely on external hydraulic or pneumatic control, resulting in complex structures and high costs. More importantly, such impact functions require operators to manually determine the activation timing based on experience, making it impossible to automatically trigger and stop based on changes in borehole load. This leads to delayed or false triggering of the impact function, making it difficult to effectively prevent drill jamming and causing unnecessary energy waste. Summary of the Invention

[0005] The purpose of this invention is to provide a power head device and drilling equipment to solve the problems existing in the prior art. It has a simple structure and low cost, and can automatically trigger and stop according to the changes in the load at the bottom of the hole, thereby reducing unnecessary energy loss.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a power head device, comprising: a fixed frame, a main shaft, a drive mechanism, a vibration actuator, a first energy storage and reset component, and a vibration transmission component; the main shaft is rotatably mounted on the fixed frame; the drive mechanism is mounted on the fixed frame and is drively connected to the main shaft for driving the main shaft to rotate; the vibration actuator is slidably sleeved on the main shaft along the axial direction and can rotate synchronously with the main shaft; the vibration actuator is used to connect to a drill bit; the first energy storage and reset component is used to apply an elastic force toward the bottom of the hole to the vibration actuator; the vibration actuator is configured to compress the first energy storage and reset component when the drill bit is subjected to rock resistance; the vibration transmission component is used to convert the vibration of the vibration transmission component into a vibration impact motion of the vibration actuator along the axial direction of the main shaft when the compression stroke of the first energy storage and reset component reaches a set threshold, so as to transmit axial vibration impact to the drill bit.

[0007] In one embodiment, the vibration transmission component includes a cam sleeve, a second energy storage and reset component, a boss, and a helical stepped surface. The cam sleeve is movably mounted on the fixed frame along the axial direction of the main shaft and sleeved outside the vibration actuator. The second energy storage and reset component applies a vibrational elastic force toward the bottom of the hole to the cam sleeve. The boss is disposed on the outer wall of the vibration actuator. The helical stepped surface is disposed on the inner wall of the cam sleeve and is an incomplete helical surface extending circumferentially along the cam sleeve. The boss is configured to contact the helical stepped surface when the compression stroke of the first energy storage and reset component reaches a set threshold, and to move relative to the helical stepped surface as the vibration actuator rotates with the main shaft, thereby driving the cam sleeve to overcome the elastic force of the second energy storage and reset component and move axially to compress the second energy storage and reset component. After the boss rotates to the end of the helical stepped surface, it disengages from the helical stepped surface, the second energy storage and reset component releases energy and drives the cam sleeve to reset axially, thereby generating an axial vibration impact on the vibration actuator, which is transmitted to the drill bit via the vibration actuator.

[0008] In one embodiment, a key is further included, which is fixedly installed on the inner wall of the excitation actuator. The main shaft is provided with an axially extending keyway, the length of which is greater than the length of the key. The key and the keyway are slidably engaged so that the excitation actuator is slidably sleeved on the main shaft along the axial direction of the main shaft and can rotate synchronously with the main shaft.

[0009] In one embodiment, the first energy storage reset member is sleeved on the spindle, one end of the first energy storage reset member abuts against the fixed frame, and the other end of the first energy storage reset member abuts against the excitation actuator to apply an elastic force toward the bottom of the hole to the excitation actuator.

[0010] In one embodiment, the second energy storage reset member is sleeved on the main shaft, one end of the second energy storage reset member abuts against the fixed frame, and the other end of the second energy storage reset member abuts against the cam sleeve to apply a spring force toward the bottom of the hole to the cam sleeve.

[0011] In one embodiment, both the first energy storage reset member and the second energy storage reset member are springs.

[0012] In one embodiment, the system further includes a plurality of first limiting rods, one end of each first limiting rod being fixedly connected to the fixed frame, and the axis of each first limiting rod being parallel to the axis of the main shaft; the other end of each first limiting rod is provided with a limiting element; the cam sleeve is slidably connected to each of the first limiting rods, each first limiting rod being used to guide the cam sleeve along the axial direction of the main shaft, and the limiting element being used to limit the reset stroke of the cam sleeve along the axial direction of the main shaft.

[0013] In one embodiment, a second guide member is further included, which is disposed between the first energy storage reset member and the second energy storage reset member and is fixedly connected to the fixed frame; the cam sleeve is slidably engaged with the second guide member, and the second guide member is used to guide the cam sleeve along the axial direction of the main shaft.

[0014] In one embodiment, the spindle has an axially extending through hole inside for a core-taking tool to pass through.

[0015] In one embodiment, the fixed frame has a guide opening at the end near the core-taking tool inlet side, corresponding to the position of the through hole. The guide opening is a tapered hole, and the diameter of the tapered hole at the end near the core-taking tool inlet side is larger than the diameter at the end away from the core-taking tool inlet side. The guide opening is used to guide the core-taking tool into the through hole.

[0016] The present invention also discloses a drilling device, including a body, a drill bit, and the aforementioned power head device, wherein the power head device is mounted on the body and the drill bit is connected to the power output end of the power head device.

[0017] The present invention achieves the following technical effects compared to the prior art: This invention discloses a power head device and drilling equipment. The main shaft drives the excitation actuator and the drill bit to rotate. The drill bit is compressed by the rock resistance, and the compression stroke of the first energy storage and reset component is compressed. When the compression stroke of the first energy storage and reset component reaches a set threshold, the vibration of the excitation transmission component is converted into the vibration impact motion of the excitation actuator along the main shaft axis to transmit axial vibration impact to the drill bit. This process does not require an additional impact power source, can be adaptively triggered according to the rock resistance, mechanically stores and releases energy and transmits energy directly. The structure is simple and low-cost. All components are coaxially assembled and the structure is compact. Therefore, it can effectively improve the drilling efficiency of hard rock formations, reduce drill bit wear and energy consumption, simplify control and adapt to different working conditions. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of one embodiment of the power head device in Example 1; Figure 2 This is a front view of the power head device in Embodiment 1; Figure 3 for Figure 2 A sectional view; In the diagram: 1. Fixed frame; 2. Spindle; 3. Drive mechanism; 4. Vibration actuator; 5. First energy storage and reset component; 6. Cam sleeve; 7. Second energy storage and reset component; 8. Boss; 9. Helical step surface; 10. First limit rod; 11. Limiting component; 12. Second guide component; 13. Through hole; 14. Guide hole; 15. Motor; 16. Driven gear; 17. Driven gear. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] The purpose of this invention is to provide a power head device and drilling equipment to solve the problems existing in the prior art. It has a simple structure and low cost, and can automatically trigger and stop according to the load changes at the bottom of the hole, thereby reducing unnecessary energy loss.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1 like Figure 1-3 As shown, this embodiment provides a power head device, including: a fixed frame 1, a main shaft 2, a drive mechanism 3, a vibration actuator 4, a first energy storage and reset component 5, and a vibration transmission component; the main shaft 2 is rotatably mounted on the fixed frame 1; the drive mechanism 3 is mounted on the fixed frame 1 and is connected to the main shaft 2 for driving the main shaft 2 to rotate; the vibration actuator 4 is slidably sleeved on the main shaft 2 along the axial direction of the main shaft 2 and can rotate synchronously with the main shaft 2; the vibration actuator 4 is used to connect to the drill bit; the first energy storage and reset component 5 is used to apply a spring force towards the bottom of the hole to the vibration actuator 4; the vibration actuator 4 is configured to compress the first energy storage and reset component 5 when the drill bit is subjected to rock resistance; the vibration transmission component is used to convert the vibration of the vibration transmission component into a vibration impact motion of the vibration actuator 4 along the axial direction of the main shaft when the compression stroke of the first energy storage and reset component 5 reaches a set threshold, so as to transmit axial vibration impact to the drill bit. The main shaft 2 drives the excitation actuator 4 and the drill bit to rotate. The drill bit is compressed by the rock resistance. When the compression stroke of the first energy storage reset component 5 reaches the set threshold, the vibration of the excitation transmission component is converted into the vibration impact motion of the excitation actuator 4 along the axial direction of the main shaft 2 to transmit axial vibration impact to the drill bit. This process does not require an additional impact power source, can be adaptively triggered by the rock resistance, mechanically stores and releases energy and transmits energy directly. It has a simple structure, low cost, and coaxial assembly of all components, making it compact. Therefore, it can effectively improve the drilling efficiency of hard rock formations, reduce drill bit wear and energy consumption, simplify control and adapt to different working conditions.

[0024] In one embodiment, the vibration transmission component includes a cam sleeve 6, a second energy storage and reset component 7, a boss 8, and a helical stepped surface 9. The cam sleeve 6 is movably mounted on the fixed frame 1 along the axial direction of the main shaft 2 and is sleeved on the outside of the vibration actuator 4. The second energy storage and reset component 7 is used to apply a vibrational elastic force toward the bottom of the hole to the cam sleeve 6. The boss 8 is disposed on the outer wall of the vibration actuator 4. The helical stepped surface 9 is disposed on the inner wall of the cam sleeve 6 and is an incomplete helical surface extending circumferentially along the cam sleeve 6. The boss 8 is configured to be in the first energy storage and reset component. When the compression stroke of component 5 reaches the set threshold, it contacts the spiral step surface 9 and moves relative to the spiral step surface 9 as the excitation actuator 4 rotates with the spindle 2, so as to drive the cam sleeve 6 to overcome the elastic force of the second energy storage reset component 7 and move axially and compress the second energy storage reset component 7; after the boss 8 rotates to the end of the spiral step surface 9, it disengages from the spiral step surface 9, the second energy storage reset component 7 releases energy and drives the cam sleeve 6 to reset axially, thereby generating axial vibration impact on the excitation actuator 4, which is transmitted to the drill bit through the excitation actuator 4.

[0025] When the compression stroke reaches the set threshold, the boss 8 contacts the spiral step surface 9 of the inner wall of the cam sleeve 6. During the rotation, the cam sleeve 6 is driven to overcome the elastic force of the second energy storage and reset component 7 and move axially to store energy. After the boss 8 rotates to the end of the spiral step surface 9 and disengages, the second energy storage and reset component 7 releases energy and drives the cam sleeve 6 to axially reset. The cam sleeve 6 impacts the excitation actuator 4, thereby generating an axial impact on the excitation actuator 4 and transmitting it to the drill bit, realizing the combined drilling of rotation and axial impact.

[0026] In one embodiment, a key is also included. The key is fixedly installed on the inner wall of the excitation actuator 4. The main shaft 2 is provided with an axially extending keyway. The length of the keyway is greater than the length of the key. The key and the keyway are slidably engaged so that the excitation actuator 4 is slidably sleeved on the main shaft 2 along the axial direction of the main shaft 2 and can rotate synchronously with the main shaft 2.

[0027] This embodiment achieves separation of torque transmission and axial sliding by using a key fixed to the inner wall of the excitation actuator 4 and a keyway extending axially on the main shaft 2 with a length greater than the key length. This allows the excitation actuator 4 to rotate synchronously with the main shaft 2 in the circumferential direction by being limited by the key and the side of the keyway, while in the axial direction it can slide along the keyway. Since the keyway length is greater than the key length, the key remains within the keyway throughout the entire axial sliding stroke. This not only ensures continuous torque transmission and circumferential phase stability, but also limits the sliding range and prevents overtravel by limiting the key at both ends of the keyway. At the same time, the guiding effect of the keyway on the key makes the axial movement of the excitation actuator 4 smooth, reducing jamming and uneven wear. Furthermore, this structure is simple and compact, easy to assemble and maintain, and the eccentricity distribution or the position of the excitation force can be changed by adjusting the axial position of the excitation actuator 4, thereby adjusting the excitation characteristics and improving the adjustability, operational stability and reliability of the excitation device.

[0028] In one embodiment, the first energy storage reset member 5 is sleeved on the spindle 2, one end of the first energy storage reset member 5 abuts against the fixed frame 1, and the other end of the first energy storage reset member 5 abuts against the excitation actuator 4 to apply a spring force toward the bottom of the hole to the excitation actuator 4.

[0029] By sleeved on the main shaft 2 with one end abutting against the fixed frame 1 and the other end abutting against the excitation actuator 4, an elastic support and force transmission path along the axial direction of the main shaft 2 is formed between the fixed frame 1 and the excitation actuator 4. The first energy storage reset component 5 stores energy under pressure and applies a spring force towards the bottom of the hole to the excitation actuator 4, enabling the excitation actuator 4 to automatically reset or continuously press against the bottom of the hole after sliding along the axial direction of the main shaft 2. Simultaneously, the first energy storage reset component 5, sleeved on the main shaft 2, serves as a guide and support, preventing the first energy storage reset component 5 from tilting or becoming unstable. This ensures the spring force is uniformly transmitted along the axial direction, resulting in a compact structure and convenient assembly. Furthermore, by selecting first energy storage reset components 5 with different stiffness or preload, the reset force and preload effect can be adjusted, allowing for automatic reset or preload, thereby improving the motion smoothness, operational reliability, and adaptability of the excitation actuator 4. In one embodiment, the second energy storage reset member 7 is sleeved on the main shaft 2, one end of the second energy storage reset member 7 abuts against the fixed frame 1, and the other end of the second energy storage reset member 7 abuts against the cam sleeve 6 to apply a spring force toward the bottom of the hole to the cam sleeve 6.

[0030] The second energy storage reset component 7 is sleeved on the main shaft 2, which can guide and support the component, preventing it from tilting or becoming unstable. This ensures that the elastic force is transmitted evenly along the axial direction. The structure is compact and easy to assemble. The pre-tightening and reset effects can be adjusted by selecting different stiffness or pre-tightening force. Together with the first energy storage reset component 5, it can apply elastic force towards the bottom of the hole to the excitation actuator 4 and the cam sleeve 6, respectively, so that each moving part maintains a certain axial fit and phase relationship, thereby improving the motion accuracy, running stability, working reliability and adaptability of the excitation device.

[0031] In one embodiment, both the first energy storage reset component 5 and the second energy storage reset component 7 are springs. Springs have simple structures, low costs, high standardization, and are easy to install and maintain.

[0032] In one embodiment, the system further includes a plurality of first limiting rods 10, one end of each first limiting rod 10 being fixedly connected to the fixed frame 1, and the axis of each first limiting rod 10 being parallel to the axis of the main shaft 2; the other end of each first limiting rod 10 is provided with a limiting element 11; the cam sleeve 6 is slidably connected to each first limiting rod 10, and each first limiting rod 10 is used to guide the cam sleeve 6 along the axial direction of the main shaft 2, and the limiting element 11 is used to limit the reset stroke of the cam sleeve 6 along the axial direction of the main shaft 2.

[0033] On the one hand, the cam sleeve 6 slides axially along each of the first limiting rods 10, which can ensure that its movement direction is consistent with the axis of the main shaft 2, avoid deviation, swinging and jamming during the movement, and improve the axial alignment accuracy and movement stability. On the other hand, the limiting member 11 at the end of the first limiting rod 10 can abut against and limit the cam sleeve 6 when it is reset towards the bottom of the hole by the action of the second energy storage reset member 7, limit its reset stroke, prevent the cam sleeve 6 from over-reset, dislodging from the first limiting rod 10 or colliding with adjacent parts, and prevent the second energy storage reset member 7 from being over-deformed, so that the cam sleeve 6 can reliably slide and reset within the set stroke.

[0034] In one embodiment, a second guide member 12 is further included. The second guide member 12 is disposed between the first energy storage reset member 5 and the second energy storage reset member 7, and is fixedly connected to the fixed frame 1. The cam sleeve 6 is slidably engaged with the second guide member 12. The second guide member 12 is used to guide the cam sleeve 6 along the axial direction of the main shaft 2. By disposing the second guide member 12 between the first energy storage reset member 5 and the second energy storage reset member 7 and fixing it to the fixed frame 1, a fixed support and separation can be formed between the first energy storage reset member 5 and the second energy storage reset member 7, avoiding mutual interference, cross-movement, or elastic force bias between the first energy storage reset member 5 and the second energy storage reset member 7, and ensuring that the first energy storage reset member 5 stably applies elastic force towards the bottom of the hole to the excitation actuator 4 and the second energy storage reset member 7 stably applies elastic force towards the bottom of the hole to the cam sleeve 6, respectively. The second guide member 12 adopts a guide cylinder, which can provide a larger guiding mating surface, and together with the first limit rod 10, forms a multi-point axial guide for the cam sleeve 6, improving the centering accuracy and stability of the cam sleeve 6 moving along the axial direction of the main shaft 2, and preventing skewing.

[0035] In one embodiment, the spindle 2 has an axially extending through hole 13 inside for a coring tool to pass through. The coring tool can be directly inserted into, pass through and extend to the bottom of the hole along the axis of the spindle 2 to perform coring operations.

[0036] In one embodiment, a guide opening is provided at the end of the fixed frame 1 near the core-taking tool inlet side, corresponding to the position of the through hole 13. The guide opening is a tapered hole, and the diameter of the tapered hole at the end near the core-taking tool inlet side is larger than the diameter at the end away from the core-taking tool inlet side. The guide opening is used to guide the core-taking tool into the through hole 13, which is simple to operate.

[0037] In one specific embodiment, the drive mechanism 3 is a motor 15. The output end of the motor 15 is connected to the drive gear 17 via a key. The drive gear 17 meshes with a driven gear 16. The driven gear 16 has a spline groove that engages with the spline on the spindle 2, thereby transmitting the rotational torque from the DC geared motor 15 to the spindle 2. By installing the drive gear 17 and the driven gear 16 in a gearbox and using dry lubrication within the gearbox, the pressure changes inside the gearbox during drilling are automatically balanced by a vent.

[0038] Example 2 This embodiment also discloses a drilling device, including a body, a drill string, and a power head device as described in Embodiment 1. The power head device is mounted on the body, and the drill string is connected to the power output end of the power head device.

[0039] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A power head device, characterized in that: include: Fixed frame; The main shaft is rotatably mounted on the fixed frame; A drive mechanism, mounted on the fixed frame and connected to the main shaft, is used to drive the main shaft to rotate. The vibration actuator is slidably sleeved on the main shaft along the axial direction of the main shaft and can rotate synchronously with the main shaft; The excitation actuator is used to connect the drilling tool; The first energy storage reset component is used to apply a spring force toward the bottom of the hole to the excitation actuator; The excitation actuator is configured to compress the first energy storage reset element when the drill bit is subjected to rock resistance; And a vibration transmission component, used to convert the vibration of the vibration transmission component into the vibration impact motion of the vibration actuator along the spindle axis when the compression stroke of the first energy storage reset component reaches a set threshold, so as to transmit axial vibration impact to the drill bit.

2. The power head device according to claim 1, characterized in that: The excitation transmission component includes a cam sleeve, which is movably mounted on the fixed frame along the axial direction of the main shaft and sleeved outside the excitation actuator; The second energy storage reset component is used to apply a vibratory elastic force toward the bottom of the hole to the cam sleeve; A boss is provided on the outer wall of the vibration actuator; And a spiral step surface, which is provided on the inner wall of the cam sleeve and is an incomplete spiral surface extending circumferentially along the cam sleeve; The boss is configured to contact the spiral step surface when the compression stroke of the first energy storage reset member reaches a set threshold, and to move relative to the spiral step surface when the excitation actuator rotates with the main shaft, so as to drive the cam sleeve to overcome the elastic force of the second energy storage reset member and move axially to compress the second energy storage reset member. After the boss rotates to the end of the spiral step surface, it disengages from the spiral step surface. The second energy storage and reset component releases energy and drives the cam sleeve to reset axially, thereby generating axial vibration impact on the excitation actuator. This impact is transmitted to the drill bit through the excitation actuator.

3. The power head device according to claim 2, characterized in that: It also includes a key, which is fixedly installed on the inner wall of the excitation actuator. The main shaft is provided with an axially extending keyway, the length of which is greater than the length of the key. The key and the keyway are slidably engaged so that the excitation actuator is slidably sleeved on the main shaft along the axial direction of the main shaft and can rotate synchronously with the main shaft.

4. The power head device according to claim 2, characterized in that: The first energy storage reset component is sleeved on the main shaft. One end of the first energy storage reset component abuts against the fixed frame, and the other end of the first energy storage reset component abuts against the excitation actuator to apply a spring force toward the bottom of the hole to the excitation actuator.

5. The power head device according to claim 2, characterized in that: The second energy storage reset component is sleeved on the main shaft. One end of the second energy storage reset component abuts against the fixed frame, and the other end of the second energy storage reset component abuts against the cam sleeve to apply a spring force toward the bottom of the hole to the cam sleeve.

6. The power head device according to claim 2, characterized in that: Both the first energy storage reset component and the second energy storage reset component are springs.

7. The power head device according to claim 2, characterized in that: It also includes a plurality of first limiting rods, one end of each first limiting rod being fixedly connected to the fixed frame, and the axis of each first limiting rod being parallel to the axis of the main shaft; the other end of each first limiting rod is provided with a limiting element; the cam sleeve is slidably connected to each of the first limiting rods, each first limiting rod being used to guide the cam sleeve along the axial direction of the main shaft, and the limiting element being used to limit the reset stroke of the cam sleeve along the axial direction of the main shaft.

8. The power head device according to claim 2, characterized in that: It also includes a second guide member, which is disposed between the first energy storage reset member and the second energy storage reset member, and is fixedly connected to the fixed frame; the cam sleeve is slidably engaged with the second guide member, and the second guide member is used to guide the cam sleeve along the axial direction of the main shaft.

9. The power head device according to claim 1, characterized in that: The spindle has an axially extending through hole inside for the core-taking tool to pass through.

10. A drilling device, characterized in that: It includes a body, a drill bit, and a power head device as described in any one of claims 1-9, wherein the power head device is mounted on the body and the drill bit is connected to the power output end of the power head device.

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