A rotary excavating tool

Abstract

The application discloses a rotary drilling tool in the technical field of engineering machinery, and aims to solve the problem that the rotary drilling head (3) of the rotary drilling tool in the prior art faces high-hardness rock layers when rotary drilling construction is performed, and high load is caused to a power head. The rotary drilling tool comprises a torque increasing device (1) for outputting amplified torque to the rotary drilling head (3), and a supporting device (2) for providing supporting torque for a speed reducer (27) in the torque increasing device (1); the supporting device (2) comprises an outer sleeve (10) and a supporting arm (21), the outer sleeve (10) drives the supporting arm (21) to support a larger radius, locks the outer sleeve (10) on a drilling hole wall (30), and the outer sleeve (10) is locked and fixed through abutting of a torque transmission block (24) and a guide rail groove (6), and the rotation of a fixed cylinder (28) relative to the drilling hole wall (30) is realized, so that the supporting torque is provided for the speed reducer (27).

Description

Technical Field

[0001] This invention relates to a rotary drilling tool, belonging to the field of engineering machinery technology. Background Technology

[0002] Rotary drilling is one of the most common methods for pile foundation construction. During rotary drilling, the drill bit faces rock formations of high hardness, placing excessive load on the power head. Increasing the torque output of the power head can strain the drill rod. Furthermore, when the drill bit breaks through hard rock, it can easily become stuck in softer strata below, causing the drill bit to jam. Additionally, impacts to the drill bit within the rock formation can cause deviations in the drilling direction, affecting the verticality of the borehole.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a rotary drilling tool that can not only meet the torque output requirements of hard rock formations, but also prevent the drill bit from getting stuck in soft formations.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0006] A rotary drilling tool includes a rotary drill rod and a rotary drill bit, and further includes a torque-enhancing device and a support device. The support device includes an outer sleeve and a support arm with an adjustable support radius. The support arm is distributed around the outer periphery of the outer sleeve. The torque-enhancing device includes a fixed sleeve. At least one of the fixed sleeve and the outer sleeve is provided with a torque-transmitting block buckle, and the other is provided with a torque-transmitting groove for the torque-transmitting block to slide. The torque-transmitting groove includes an upper slot, a lower slot, and a guide rail groove connecting the upper slot and the lower slot. The upper slot and the lower slot are used to restrict the vertical movement of the torque-transmitting block after it slides in, thereby restricting the relative vertical movement of the fixed sleeve and the outer sleeve. The outer sleeve can follow the fixed sleeve to move vertically within the rotary drilling hole.

[0007] When the torque transmission block is in the lower slot, the torque amplifying device can drive the outer sleeve to move synchronously under the drive of the rotary drill rod. The support arm can adjust the support radius according to the borehole diameter under the drive of the outer sleeve, so that the outer sleeve supports and locks in the borehole. When the torque transmission block is in the guide rail groove, the torque amplifying device amplifies the torque output by the rotary drill rod and transmits it to the rotary drill bit to drive the rotary drill bit to perform drilling operations. When the torque transmission block is in the upper slot, the outer sleeve can drive the support arm to disengage from the borehole under the drive of the torque amplifying device, thereby enabling the rotary drill rod to perform a drill lifting operation.

[0008] Furthermore, the support device also includes a first fixing sleeve and a second fixing sleeve sleeved on the outer periphery of the outer sleeve; one end of the support arm is hinged to the first fixing sleeve and the other end is hinged to the second fixing sleeve;

[0009] When the outer sleeve moves up and down with the torque-increasing device, it can drive the second fixed sleeve away from or closer to the first fixed sleeve, so that the support radius of the support arm expands and embeds into the borehole wall 30.

[0010] Furthermore, the support arm includes a first support rod hinged to the first fixed sleeve and a second support rod hinged to the second fixed sleeve;

[0011] The first support rod and the second support rod are hinged together, and a support block is provided at the hinge point.

[0012] When the outer sleeve moves downward with the torque-increasing device into the borehole, the support block contacts the borehole wall and is subjected to frictional force from the borehole wall. The support arm unfolds and its diameter increases under the push of the support block until the outer sleeve is fixed relative to the borehole wall. At this time, the torque-transmitting block and the guide rail groove abut against each other, and the fixed cylinder cannot rotate relative to the borehole wall. When the outer sleeve moves upward with the torque-increasing device and exits the borehole, the support block gradually detaches from the borehole wall, and the support arm retracts until its diameter is smaller than the borehole diameter, and the support block detaches from the borehole wall.

[0013] Furthermore, the support block is provided with multiple alloy cones to increase the friction coefficient of the support block.

[0014] Furthermore, the second fixing sleeve has a pin at one end near the rotary drill bit, a stop groove on one side of the pin, and a second stepped surface on the outer sleeve. When the second stepped surface is engaged in the stop groove, the outer sleeve is locked in the borehole.

[0015] The second stepped surface prevents the second fixing sleeve from coming off the outer sleeve.

[0016] Furthermore, the outer sleeve is provided with a limiting step to prevent the first fixed sleeve from sliding downwards, and the upper end of the first fixed sleeve is also provided with a first step surface to prevent the first fixed sleeve from falling out. At least one of the first step surface and the first fixed sleeve is provided with a stop block, and the other is provided with a stop groove to restrict the rotation of the stop block.

[0017] When the stop block is restricted from rotating by the stop groove, the outer sleeve is locked inside the drill hole; the first stepped surface prevents the first fixing sleeve from coming out of the outer sleeve.

[0018] Furthermore, the torque transmission block is disposed on the inner wall of the outer sleeve, the torque transmission groove is disposed on the outer wall of the fixed cylinder, the lower side of the torque transmission block is a slope surface, and the upper slot is provided with a slope surface matching the slope surface of the torque transmission block on the side near the lower slot.

[0019] The torsion block can slide upward along the slope into the upper slot, and the fixed cylinder moves downward relative to the outer sleeve.

[0020] Furthermore, the upper slot extends to the upper end face of the fixed cylinder, and an end cap is detachably connected to the upper end face of the fixed cylinder.

[0021] After the end cap is removed, the torque transmission block enters the torque transmission groove through the opening on the upper end face of the fixed cylinder via the upper slot; after the end cap is installed, the torque transmission block cannot be dislodged from the torque transmission groove; thus realizing the disassembly and assembly of the outer sleeve and the fixed cylinder.

[0022] Furthermore, the end of the torque-increasing device connected to the rotary drilling rod is provided with a first square head, and the rotary drilling rod is connected to the torque-increasing device through the first square head.

[0023] Furthermore, the end of the torque-increasing device connected to the rotary drilling bit is provided with a second square head, and the end of the rotary drilling bit near the torque-increasing device is provided with a third third head, which can extend into the second square head and slide relative to the second square head;

[0024] A limiting plate is detachably connected to the second square head to prevent the third third head from detaching from the second square head.

[0025] By adjusting the size of the limiting plate to match the third-party head, the compatibility of the second-party head is improved.

[0026] Compared with the prior art, the present invention reduces manufacturing costs while increasing torque by setting a torque-increasing device connected to the rotary drilling bit drive. When the outer sleeve is locked on the borehole wall, the cooperation between the torque-transmitting block and the guide rail groove prevents the rotation of the fixed cylinder, ensuring the torque output of the torque-increasing device. It also prevents the rotary drilling bit from getting stuck in soft strata after breaking through hard rock layers. At the same time, the outer sleeve is fitted outside the fixed cylinder, which guides the drilling of the rotary drilling bit. Furthermore, a detachable limiting plate is set on the second side to ensure the compatibility of the torque-increasing device with different rotary drilling bits. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the rotary drilling tool provided in the embodiment in its initial state;

[0028] Figure 2 yes Figure 1 Schematic diagram of the torque-increasing device;

[0029] Figure 3 It is along Figure 2 Cross-sectional view of the central axis of the torque-increasing device;

[0030] Figure 4 yes Figure 1 A schematic diagram of the structure of the central support device in its initial state;

[0031] Figure 5 yes Figure 4 Internal cross-sectional view of the central support device, showing the position of the torsion block;

[0032] Figure 6 yes Figure 1 Schematic diagram of the structure of a rotary drilling bit;

[0033] Figure 7 This is a schematic diagram of the rotary drilling tool in use provided in the embodiment;

[0034] Figure 8 This is a schematic diagram of the transmission torsion block sliding into the lower slot;

[0035] Figure 9 This is a schematic diagram of the transmission torsion block guide rail groove sliding to the upper slot;

[0036] Figure 10 yes Figure 1 A front view of the rotary drilling tool when the outer sleeve is locked inside the borehole wall and the transmission block is located in the guide rail groove during normal operation;

[0037] Figure 11 yes Figure 1 A cross-sectional view showing the middle third head and the second third head slidingly connected and restricted from detachment by a limiting plate;

[0038] In the diagram: Torque amplification device-1; Support device-2; Rotary drilling bit-3; First square head-4; Second square head-5; Guide rail groove-6; Upper slot-7; Lower slot-8; End cap-9; Outer sleeve-10; Upper fixing sleeve-11; Lower fixing sleeve-12; Upper step surface-13; Lower step surface-14; Stop block-15; Stop groove-16; Limiting step-17; Ejector pin-18; Stop groove-19; Hinge point-20; Support arm-21; Support block-22; Alloy cone head-23; Torque transmission block-24; Third square head-25; Limiting plate-26; Reducer-27; Fixed cylinder-28; Rotary drilling rod-29; Borehole wall-30. Implementation

[0039] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments and specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations thereof. In the absence of conflict, the embodiments and technical features in the embodiments can be combined with each other. Example 1

[0040] Based on this application, this embodiment provides a rotary drilling tool applicable to rotary drilling rigs, see reference. Figure 1 and Figure 3 The first square head 4 located at the input end of the torque amplification device 1 is connected to the rotary drill rod 29 for transmission. The torque amplification device 1 amplifies the torque of the rotary drill rod 29 and outputs it to the rotary drill bit 3. The torque amplification device 2 includes a fixed cylinder 28. As is known from the prior art, the torque amplification device 2 needs to provide support torque to the reducer 27 when it is in operation, that is, to prevent the fixed cylinder 28 from rotating relative to the borehole wall 30.

[0041] To ensure that the torque-increasing device 2 provides supporting torque to the self-reducing motor 27 via the fixed cylinder 28 during operation and to prevent the fixed cylinder 28 from rotating relative to the borehole wall 30, a support device 2 is sleeved on the outer side of the fixed cylinder 28; Reference Figure 4 and Figure 7 The support device 2 includes an outer sleeve 10 sleeved on the outside of the torque amplifying device 1. When the torque amplifying device 2 is in operation, the outer sleeve 10 can prevent the relative rotation between the fixed cylinder 28 and the borehole wall 30, thereby providing support torque to the self-reducing gear 27. The torque amplifying device 1 can drive the outer sleeve 10 to move synchronously under the drive of the rotary drill rod 29. Support arms 21 with adjustable support radii according to the borehole diameter are distributed on the outside of the outer sleeve 10. The support arms 21 adjust the support radius under the drive of the outer sleeve 10. The support arms 21 unfold and embed into the borehole wall 30, and transmit support torque to the fixed cylinder 28 by restricting the rotation of the outer sleeve 10 relative to the borehole wall 30. The support arms 21 retract and the outer sleeve 10 is removed from the borehole.

[0042] When the torque-enhancing device 1 is in operation, the rotary drill bit 3 drills downwards, causing the fixed cylinder 28 to move downwards relative to the outer sleeve 10; when the drill is pulled up, the fixed cylinder 28 needs to maintain a fixed vertical position relative to the outer sleeve 10; therefore, refer to Figure 2 The outer surface of the torque-increasing device 1 includes a fixed cylinder 28; at least one of the fixed cylinder 28 and the outer sleeve 10 is provided with a torque-transmitting block 24, and the other is provided with a torque-transmitting groove for the torque-transmitting block 24 to slide; simultaneously refer to Figure 5 In this embodiment, to prevent stress concentration points from appearing in the outer sleeve 10, complex structures should not be provided on the inner side of the outer sleeve 10. Therefore, a simple-shaped torque transmission block 24 is placed on the inner side of the outer sleeve 10, and a torque transmission groove is placed on the outer side of the fixed cylinder 28. According to the upper and lower positions, the torque transmission groove includes an upper slot 7 and a lower slot 8, and also includes a guide rail groove 6 arranged along the axial direction of the rotary drilling rod 29. The guide rail groove 6 connects the upper slot 7 and the lower slot 8. When the torque transmission block 24 is located in the guide rail groove 6, the two sides of the torque transmission block 24 are abutted by the fixed cylinder 28. The fixed cylinder 28 cannot rotate relative to the outer sleeve 10 but can rotate relative to the upper sleeve 28. As the rotary drill bit 3 slides downward, it drives the torque-increasing device 1 to move downward relative to the outer sleeve 10. The guide rail groove 6 can also prevent the torque-transmitting block 24 from falling out of the fixed sleeve 28, thus preventing the rotary drill bit 3 from getting stuck in soft strata after breaking through hard rock. The guide rail groove 6, which is set along the axial direction of the rotary drill rod 29, restricts the sliding of the torque-transmitting block 24 and guides the rotary drill bit 3 to drill. When the torque-transmitting block 24 is in the upper slot 7 or the lower slot 8, the fixed sleeve 28 needs to be fixed in the upper and lower positions relative to the outer sleeve 10. The drill can be lifted at this time.

[0043] To enable the support arm 21 to adjust its support radius under the drive of the outer sleeve 10, refer to Figure 4 The support device 2 includes a first fixed sleeve 11 and a second fixed sleeve 12 sleeved around the outer periphery of the outer sleeve 10. The two ends of the support arm 21 are respectively hinged to the first fixed sleeve 11 and the second fixed sleeve 12. When the outer sleeve 10 moves up and down with the torque-increasing device 1, it can drive the second fixed sleeve 12 away from or close to the first fixed sleeve 11 and change the rod structure of the support arm 21 so that the support radius of the support arm 21 expands and embeds into the borehole wall 30 until it is embedded into the borehole wall 30. In this embodiment, since the environment is harsh during rotary drilling, the hinge relationship of the support arm 21 should not be too many. Therefore, the support arm 21 is designed simply. The support arm 21 includes a first support rod hinged to the first fixed sleeve 11 and a second support rod hinged to the second fixed sleeve 12. The first support rod and the second support rod are hinged at the hinge point 20. The hinge point 20 is also hinged to a support block 22 to increase the friction area between the support arm 21 and the borehole wall 30 to improve the support capacity of the support device 2.

[0044] refer to Figure 7 and Figure 3When the support arm 21 descends with the outer sleeve 10 within the borehole wall 30, the support block 22 contacts the borehole wall 30 and experiences an upward frictional force along the borehole wall 30, causing the outer sleeve 10 to move downward relative to the support block 22. Based on the nature of the rod structure, the support arm 21 unfolds, its support radius increases, pushing the support block 22 further into the borehole wall 30 and subjecting it to greater frictional force, until the frictional force on the support arm 21 is sufficient to support the weight of the outer sleeve 10 and simultaneously provide support torque for the reducer 27. During this process, the second support rod slides upward toward the first support rod to adapt to the change in the rod structure.

[0045] refer to Figure 4 The upper and lower ends of the outer sleeve 10 are respectively provided with a first step surface 13 and a second step surface 14 to prevent the first fixed sleeve 11 and the second fixed sleeve 12 from falling out. At the same time, in order to prevent the first fixed sleeve 11 from sliding down, the outer sleeve 10 is also provided with a limiting step 17 on the other side of the first fixed sleeve 11 relative to the first step surface 13.

[0046] To prevent relative rotation between the outer sleeve 10 and the first fixed sleeve 11 and the second fixed sleeve 12 during the operation of the torque-increasing device 1, at least one of the first stepped surface 13 and the first fixed sleeve 11 is provided with a stop 15, and the other is provided with a stop groove 16 to restrict the rotation of the stop 15. In this embodiment, considering that the outer sleeve 10 is cast due to its complex shape, while the first fixed sleeve 11 has a simple shape and can be manufactured as a finished product, and that the stop 15 will be subjected to a large shear stress from the outer sleeve 10, refer to... Figure 4 Therefore, a notch is cut at the upper end of the first fixed sleeve 11 to form a retaining groove 16, and the first step surface 13 is cast to protrude towards the side close to the first fixed sleeve 11 to form a retaining block 15. In this embodiment, in order to match the position of the anti-rotation groove 19, the retaining block 15 is set to the position where the rotation of the outer sleeve 10 relative to the drill hole is prevented when it abuts against the side of the retaining groove 16 in the forward rotation direction.

[0047] refer to Figure 4 The second fixing sleeve 12 is provided with a pin 18 at one end near the rotary drill bit 3, for reference. Figure 8 In the initial state, the transmission block 24 is located in the lower slot 8, as shown in the reference. Figure 1 At this time, the ejector pin 18 passes through the gap in the second fixed sleeve 12 and presses against the rotary drill bit 3; an anti-rotation groove 19 is provided on one side of the ejector pin 18. When the rotary drill rod 29 rotates forward, the outer sleeve 10 rotates forward synchronously. The second step surface 14 is engaged in the anti-rotation groove 14 and is held by the ejector pin 18. Due to the friction of the support arm 21 against the borehole wall 30, the rotation of the outer sleeve 10 relative to the borehole wall 30 is locked. In this embodiment, considering better cooperation with the upper slot 7 and the lower slot 8, the anti-rotation groove 19 is provided on the side of the ejector pin 18 away from the forward rotation direction of the rotary drill rod 29. When the second step surface 14 is engaged in the anti-rotation groove 14 and is held by the ejector pin 18, the stop block 15 is simultaneously held by the stop groove 16.

[0048] Based on the above, the following work schedule is obtained:

[0049] a) Reference Figure 8 In the initial state, the transmission block 24 is located in the lower slot 8, as shown in the reference. Figure 1 At this time, because the vertical movement of the transmission block 24 is restricted, the outer sleeve 10 and the fixed sleeve 28 remain relatively fixed; Reference Figure 7 When the outer sleeve 10 moves downward with the torque-increasing device 1, the support block 22 contacts the borehole wall 30 and is subjected to frictional force upward along the borehole wall 30. Under the action of friction, the support block 22 moves upward relative to the outer sleeve 10. Based on the nature of the rod structure, the support arm 21 unfolds, and the second support rod drives the second fixed sleeve 12 to slide upward and gradually approach the first fixed sleeve 11. The unfolding radius of the support arm 21 increases with the downward movement of the outer sleeve 10. The support block 22 is embedded in the borehole wall 30 until the frictional force is sufficient to support the weight of the outer sleeve 10 and provide support torque for the reducer 27, and lock the movement of the outer sleeve 10 relative to the rotary drilling hole.

[0050] b) With the support device 2 in a rotated, unlocked state, the rotary drill rod 29 drives the fixed cylinder 28 to rotate clockwise, and the transmission block 24 rotates from the lower slot 8 into the guide rail slot 6, releasing the restriction on the vertical displacement of the transmission block 24; the fixed cylinder 28, through the transmission block 24, abuts against the guide rail slot 6, driving the outer sleeve 10 to rotate clockwise, as shown in the reference. Figure 7 The second step surface 14 rotates forward synchronously until it is inserted into the anti-rotation groove 19 and is stopped by the ejector pin 18; at the same time, the stop block 15 rotates forward until it is stopped by the stop groove 16; the support device 2 is in a rotational locking state, and the outer sleeve 10 and the first fixed sleeve 11 and the second fixed sleeve 12 cannot rotate relative to each other.

[0051] c) The rotary drill rod 29 continues to rotate clockwise, the support device 2 remains in the rotation-locked state, and the torque-increasing device 1 begins normal operation, outputting the increased torque to the rotary drill bit 3; (Reference) Figure 10 As the rotary drill bit 3 moves downward, the torque transmission block 24 slides upward relative to the guide rail groove 6, and the torque increasing device 1 moves downward relative to the fixed cylinder 28.

[0052] d) When the torque transmission block 24 slides close to the upper slot 7, the torque-increasing device 1 ends its operation. The rotary drill rod 29 drives the fixed cylinder 28 to reverse, and the torque transmission block 24 slides relative to the upper slot 7. The outer sleeve 10 can no longer move up and down relative to the fixed cylinder 28. At this time, the rotary drill rod 29 continues to reverse and applies a larger axial load downward. The axial load on the rotary drill bit 3 increases, and the friction between it and the bottom of the borehole gradually increases. The required support torque of the reducer 27 begins to rise. When the friction between the rotary drill bit 3 and the bottom of the borehole is greater than the friction between the outer sleeve 10 and the first fixed sleeve 11 and the second fixed sleeve 12, the outer sleeve 10 and the first fixed sleeve 11 and the second fixed sleeve 12... The friction between the fixed sleeves 12 cannot meet the support torque requirements of the reducer 27. Based on the nature of the reducer 27, the outer sleeve 10 is reversed relative to the first fixed sleeve 11 and the second fixed sleeve 12. The stop block 15 rotates to the side of the reverse direction of the stop groove 16, and the second step surface 14 disengages from the anti-rotation groove 19. The support device 2 returns to the rotating unlocked state. The rotary drilling rod 29 is slightly lifted upward, which drives the outer sleeve 10 to move upward and pass through the first support rod. The radius of the support arm 21 is reduced until it is smaller than the borehole diameter. The support block 22 disengages from the borehole wall 30. Under its own gravity, the second fixed sleeve 22 moves further away from the first fixed sleeve 21, and the support arm 21 retracts.

[0053] e) The rotary drill rod 29 drives the fixed cylinder 28 to rotate forward, and the transmission block 24 slides relative to the guide rail groove 6. The rotary drill rod 29 is lifted until the transmission block 24 approaches the lower chuck 8. The rotary drill rod 29 drives the fixed cylinder 28 to rotate in reverse, and the transmission block 24 slides relative to the lower chuck 8. At this time, the rotary drill tool returns to the state of step a).

[0054] After completing step e), the drill can be lifted or the drilling process can continue downwards.

[0055] To simplify the adjusted step d) and prevent damage to the support device 2 when the rotary drill rod 29 applies a larger axial load, a further design of the torque transmission groove and torque transmission block 24 is implemented to replace the rotary drill rod 29 in applying a larger axial load to the rotary drill bit 3: the lower side of the torque transmission block 24 is set as a slope, and the upper slot 7 has a slope matching the slope of the torque transmission block 24 on the side near the lower slot 8; Reference Figure 9 When the transmission block 24 slides close to the upper slot 7, the rotary drill rod 29 drives the fixed cylinder 28 to reverse. The transmission block 24 slides upward along the slope into the upper slot 7, and the fixed cylinder 28 moves downward relative to the outer sleeve 10. At this time, the rotary drill bit 3 is subjected to an axial load from the fixed cylinder 28. During this process, the rotary drill rod 29 does not need to apply a larger load.

[0056] The above individual work schedules are for reference only and can be used as needed.

[0057] For easier disassembly and assembly of the outer sleeve 10, please refer to... Figure 2 , Figure 7 or Figure 8 The upper slot 7 extends to the upper end face of the fixed cylinder 28, and the upper end face of the fixed cylinder 28 is detachably connected to the end cover 9. After the end cover 9 is removed, the torque transmission block 24 enters the torque transmission groove through the opening of the upper slot 7 on the upper end face of the fixed cylinder 28. After the end cover 9 is installed, the end cover 9 prevents the torque transmission block 24 from coming out of the torque transmission groove. In this embodiment, the end cover 9 is detachably connected to the fixed cylinder 28 by bolts, but other detachable connection methods can also be used. Example 2

[0058] This embodiment provides a rotary drilling tool as a functional alternative to Embodiment 1, and differs from Embodiment 1 in the following ways:

[0059] The torque transmission block is located on the outside of the fixed cylinder, and the torque transmission groove is located on the inside of the outer sleeve; the stop block is located on the upper end of the first fixed sleeve, and the stop groove is located on the side of the first step surface close to the first fixed sleeve; based on embodiment one, the same principle will not be repeated here. Example 3

[0060] This embodiment provides a rotary drilling tool that is further improved based on Embodiment 1 or 2, which improves the compatibility of the torque-enhancing device 1 with different rotary drilling bits 3.

[0061] In addition to all the technical solutions described in Embodiment 1 or 2, it also includes: references Figure 5 and Figure 6 The torque output end of the torque-enhancing device 1 is connected to the third head 25 of the rotary drilling bit 3 through the second square head 5. The third head 25 extends into the second square head 5 and can slide relative to the second square head 5 vertically. The end of the second square head 5 is provided with a detachable limit plate 26 to prevent the third head 25 from coming out of the second square head 5. By replacing the limit plate 26 of different sizes, the second square head 5 can be matched with the third head 25 of different sizes, so that the torque-enhancing device 1 can be connected to rotary drilling bits 3 of different diameters, sizes, manufacturers, models and types.

[0062] In this embodiment, the limiting plate 26 is detachably connected to the second square head 5 by bolts, but other methods may also be used.

[0063] The rotary drilling tool provided in this embodiment expands its application range and makes it easier to popularize and promote by setting a detachable limiting plate 26 on the second square head 5 to enable the torque increasing device 1 to match different rotary drilling bits 3.

[0064] refer to Figure 3 For ease of manufacturing, the speed reducer 27 used in the torque increasing device 1 in the above embodiments is a planetary gear reducer with the gear ring located inside the fixed cylinder 28, but it can also be set as other types of speed reducers 27.

[0065] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0066] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0067] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A rotary drilling tool, comprising a rotary drill rod (29) and a rotary drill bit (3), characterized in that, It also includes a torque-increasing device (1) and a support device (2), wherein the support device (2) includes an outer sleeve (10) and a support arm (21) with an adjustable support radius; the support arm (21) is distributed on the outer periphery of the outer sleeve (10); the torque-increasing device (1) includes a fixed sleeve (28). At least one of the fixed cylinder (28) and the outer sleeve (10) is provided with a torque transmission block (24), and the other is provided with a torque transmission groove for the torque transmission block (24) to slide. The torque transmission groove includes an upper slot (7), a lower slot (8) and a guide rail groove (6) connecting the upper slot (7) and the lower slot (8). When the torque transmission block (24) is in the lower slot (8), the torque amplifying device (1) drives the outer sleeve (10) to move downward synchronously under the drive of the rotary drilling rod (29), and the support radius of the support arm (21) gradually expands until the outer sleeve (10) is supported and locked in the borehole; when the torque transmission block (24) is in the guide rail groove (6), the torque amplifying device (1) amplifies the torque output by the rotary drilling rod (29) and transmits it to the rotary drilling bit (3) to drive the rotary drilling bit (3) to perform drilling operations; when the torque transmission block (24) is in the upper slot (7), the torque amplifying device (1) drives the outer sleeve (10) to move upward synchronously under the drive of the rotary drilling rod (29), and the support radius of the support arm (21) gradually shrinks until it is dislodged from the borehole; The support device (2) further includes a first fixed sleeve (11) and a second fixed sleeve (12) sleeved on the outer periphery of the outer sleeve (10); one end of the support arm (21) is hinged to the first fixed sleeve (11) and the other end is hinged to the second fixed sleeve (12); When the outer sleeve (10) moves up and down with the torque-increasing device (1), it can drive the second fixed sleeve (12) away from or close to the first fixed sleeve (11), so that the support radius of the support arm (21) can be expanded and embedded into the borehole wall (30). The support arm (21) includes a first support rod hinged to the first fixed sleeve (11) and a second support rod hinged to the second fixed sleeve (12); The first support rod and the second support rod are hinged together, and a support block (22) is provided at the hinge point (20). When the outer sleeve (10) moves downward with the torque-increasing device into the borehole, the support block (22) contacts the borehole wall (30) and is subjected to frictional force from the borehole wall. The support arm (21) unfolds and its diameter increases under the push of the support block (22) until the outer sleeve (10) is fixed relative to the borehole wall (30). At this time, the torque-transmitting block and the guide rail groove abut against each other, and the fixed sleeve cannot rotate relative to the borehole wall (30). When the outer sleeve (10) moves upward with the torque-increasing device and comes out of the borehole, the support block (22) gradually separates from the borehole wall (30), and the support arm (21) retracts until the diameter of the support arm (21) is smaller than the borehole diameter, and the support block (22) separates from the borehole wall (30).

2. The rotary drilling tool according to claim 1, characterized in that, The support block (22) is provided with multiple alloy cones (23).

3. The rotary drilling tool according to claim 1, characterized in that, The second fixing sleeve (12) has a pin (18) at one end near the rotary drill bit (3), and a stop groove (19) is provided on one side of the pin (18). The outer sleeve (10) has a second step surface (14). When the second step surface (14) is inserted into the stop groove (19), the outer sleeve (10) is locked in the borehole.

4. The rotary drilling tool according to claim 1 or 3, characterized in that, The outer sleeve is provided with a limiting step (17) to prevent the first fixed sleeve (11) from sliding downward. The upper end of the first fixed sleeve is also provided with a first step surface (13). At least one of the first step surface (13) and the first fixed sleeve (11) is provided with a stop block (15), and the other is provided with a stop groove (16) to restrict the rotation of the stop block (15).

5. The rotary drilling tool according to claim 1, characterized in that, The torsion transmission block (24) is disposed on the inner wall of the outer sleeve (10), the torsion transmission groove is disposed on the outer wall of the fixed sleeve (28), the lower side of the torsion transmission block (24) is a slope surface, and the upper slot (7) is provided with a slope surface that matches the slope surface of the torsion transmission block (24) on the side near the lower slot (8).

6. The rotary drilling tool according to claim 1 or 5, characterized in that, The upper slot (7) extends to the upper end face of the fixed cylinder (28), and the upper end face of the fixed cylinder (28) is detachably connected to an end cap (9).

7. The rotary drilling tool according to claim 1, characterized in that, The torque-increasing device (1) is connected to the rotary drilling rod (29) at one end with a first square head (4), and the rotary drilling rod (29) is connected to the torque-increasing device (1) through the first square head (4).

8. The rotary drilling tool according to claim 1 or 7, characterized in that, The torque-increasing device (1) is connected to the rotary drilling bit (3) at one end with a second square head (5), and the rotary drilling bit (3) is provided with a third third head (25) at one end near the torque-increasing device (1). The third third head (25) extends into the second square head (5) and slides relative to the second square head (5). A limiting plate (26) is detachably connected to the second square head (5) to restrict the third third head (25) from coming out of the second square head (5).

Images