A detachable variable diameter drill bit

Abstract

This invention belongs to the field of drill bit technology, specifically a detachable variable diameter drill bit, including a drill rod; a tapered drill bit is fixedly connected to the bottom of the drill rod; multiple support rods arranged in a circumferential array are provided on the side wall of the drill rod; the ends of the support rods are all fixedly connected to the outer ring of the drill bit; the outer ring of the drill bit is concentrically arranged with the drill rod; a fixing plate is fixedly connected to the outer side wall of the outer ring of the drill bit by fixing bolts; by setting a detachable reaming plate on the outer side wall of the outer ring of the drill bit, the reaming plate is installed in the first half of the pile pit construction to excavate the pile pit, and after the excavation is completed, the reaming plate is removed to continue the excavation of the pile pit. This structural design realizes the function of reducing the steps of moving the machine and changing the drill bit, effectively solving the problem that when constructing a pile pit, it is necessary to move the reverse circulation drilling machine and then change the drill bit of the reverse circulation drilling machine, which makes the construction process more complicated and affects the construction efficiency of the pile pit.

Description

Technical Field

[0001] This invention belongs to the field of drill bit technology, specifically a detachable variable diameter drill bit. Background Technology

[0002] During bridge construction, when constructing the bridge pile foundation, the expanded bearing plate pile is a type of reinforced concrete cast-in-place pile. Depending on the geological conditions, it is constructed in hard soil layers through hydraulic expansion, applying static pressure in all directions to the soil around each branch and bearing plate, thus expanding the cavity of the bearing plate pile. The compacted surrounding soil is tightly integrated with the concrete pile body and bearing plate poured into the cavity, forming an expanded bearing plate pile.

[0003] By using the technology of expanding and sizing bearing piles, the bearing capacity of the foundation soil layer can be fully utilized. This can effectively reduce the pile diameter and length while significantly increasing the pile bearing capacity and reducing pile settlement. When constructing expanding and sizing bearing piles, reverse circulation drilling rigs are usually used in conjunction with expanding and sizing bearing equipment.

[0004] When using traditional methods to construct variable cross-section extrusion-expanded bearing piles, and when there are a large number of such piles, the reverse circulation drilling rig needs to be moved from the large-diameter pile to the small-diameter pile transition point, and then the drill bit of the reverse circulation drilling rig needs to be replaced. This method results in a more complicated construction process, lower construction efficiency, and potential quality issues such as misalignment of the hole centering position.

[0005] Therefore, the present invention provides a detachable variable diameter drill bit. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is as follows: A detachable variable diameter drill bit of this invention includes a drill rod; a conical drill bit is fixedly connected to the bottom of the drill rod; multiple support rods arranged in a circumferential array are provided on the side wall of the drill rod; the ends of the support rods are all fixedly connected to the outer ring of the drill bit; the outer ring of the drill bit and the drill rod are concentrically arranged; a fixing plate is fixedly connected to the outer side wall of the outer ring of the drill bit by fixing bolts; the fixing plate is in contact with the outer ring of the drill bit; a reaming plate is fixedly connected to the outer side wall of the fixing plate; multiple first drill teeth are fixedly connected to the side wall of the reaming plate, and the first drill teeth are set on the side wall of the reaming plate corresponding to the rotation direction of the drill rod; multiple second drill teeth are fixedly connected to the bottom positions of the conical drill bit and the support rods; This effectively solves the problem that when constructing pile pits, it is necessary to move the reverse circulation drilling machine and then replace the drill bit of the reverse circulation drilling machine, which leads to a complicated construction process and affects the construction efficiency of the pile pit.

[0008] Preferably, a plug is fixedly connected to the top of the second drill bit; a fixing protrusion is slidably connected inside the support rod; an anti-detachment block is fixedly connected to the side wall of the fixing protrusion; the anti-detachment block is slidably connected inside the support rod; a spring is fixedly connected between the fixing protrusion and the side wall of the support rod; a groove is provided on the side wall of the plug at the position corresponding to the fixing protrusion; effectively preventing the fixing protrusion from detaching from the support rod.

[0009] Preferably, a guide plate is provided at the bottom of the drill rod; the bottom of the guide plate is inclined, with the highest point near the outer side of the drill rod and the lowest point away from the outer side of the drill rod; this makes the drilling direction of the drill bit more accurate.

[0010] Preferably, an air duct is provided between the slot of the insert block and the sliding cavity of the guide plate; multiple springs are fixedly connected between the top of the guide plate and the drill rod; this allows the guide plate to guide the descent of the drill rod.

[0011] Preferably, a support ring is fixed to the outer wall of the drill rod; a connecting cable is fixed between the fixing nut corresponding to the fixing bolt and the support ring; a support plate is fixed to the side wall of the nut of the fixing bolt by a spring; the support plate is set at the position corresponding to the screw of the fixing bolt; this can make the fixing bolt fix the fixing plate better.

[0012] Preferably, a positioning rod is fixedly connected inside the sliding cavity of the guide plate; the positioning rod is slidably connected inside the guide plate; the positioning rod is arranged parallel to the sliding direction of the guide plate; so that the guide plate can better maintain stability during the sliding process.

[0013] Preferably, a blocking block is fixed to the end of the positioning rod; a sliding cavity is provided at the corresponding position inside the guide plate; this can effectively prevent the guide plate from falling out of the drill rod.

[0014] Preferably, a threaded plate is fixed to the side wall of the drill rod; the threaded plate is located near the top of the outer ring of the drill bit; multiple slots are formed on the threaded plate; this can effectively prevent the threaded plate from affecting the lifting of the drill rod.

[0015] Preferably, a rubber sheet is fixed to the side wall of the insert block; the rubber sheet is disposed on the side wall where each insert block contacts the slot; this can improve the fixing effect of the fixing protrusion on the insert block.

[0016] Preferably, the blocking block has a ball bearing engaged internally; the sidewall of the ball bearing contacts the sidewall of the sliding cavity of the blocking block; thus reducing wear between the guide plate and the blocking block.

[0017] The beneficial effects of this invention are as follows:

[0018] 1. The present invention discloses a detachable variable diameter drill bit, which features a detachable reaming plate installed on the outer wall of the drill bit's outer ring. The reaming plate is installed during the first half of the pile pit construction, and the pile pit is excavated. After excavation, the reaming plate is removed to continue excavating the pile pit. This structural design reduces the steps of moving the drilling rig and changing the drill bit, effectively solving the problem that the construction process is complex and affects the efficiency of pile pit construction, as it requires moving the reverse circulation drilling rig and changing its drill bit during pile pit construction.

[0019] 2. The detachable variable diameter drill bit of the present invention, by inserting the insert block into the interior of the support rod and then fixing the second drill tooth by the fixing protrusion, realizes the function of more convenient replacement of the second drill tooth, making the replacement of the second drill tooth more convenient. At the same time, the position of the fixing protrusion can be adjusted, thereby effectively preventing the second drill tooth from tilting and falling off less often during the use of the drill bit. Attached Figure Description

[0020] The invention will now be further described with reference to the accompanying drawings.

[0021] Figure 1 This is a perspective view of the present invention;

[0022] Figure 2 This is a partial structural schematic diagram of the support ring of the present invention;

[0023] Figure 3 This is a cross-sectional view of the drill pipe in this invention;

[0024] Figure 4 yes Figure 3 Enlarged view of the local structure at point A;

[0025] Figure 5 This is a cross-sectional view of the support rod in this invention;

[0026] Figure 6 yes Figure 5 Enlarged view of the local structure at point B;

[0027] Figure 7 This is a three-dimensional schematic diagram of the fixing bolt in this invention.

[0028] In the diagram: 1. Drill rod; 2. Tapered drill bit; 3. Support rod; 4. Outer ring of drill bit; 5. Fixing plate; 6. Fixing bolt; 601. Support plate; 7. Reamer plate; 8. First drill tooth; 9. Second drill tooth; 901. Fixing protrusion; 902. Anti-detachment block; 10. Insertion block; 11. Guide plate; 12. Air duct; 13. Support ring; 14. Connecting cable; 15. Positioning rod; 16. Blocking block; 17. Threaded plate; 18. Rubber sheet; 19. Ball bearing. Detailed Implementation

[0029] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0030] like Figures 1 to 2 As shown in the embodiment of the present invention, a detachable variable diameter drill bit includes a drill rod 1; a tapered drill bit 2 is fixedly connected to the bottom of the drill rod 1; multiple support rods 3 arranged in a circumferential array are provided on the side wall of the drill rod 1; the ends of the support rods 3 are all fixedly connected to a drill bit outer ring 4; the drill bit outer ring 4 is concentrically arranged with the drill rod 1; a fixing plate 5 is fixedly connected to the outer side wall of the drill bit outer ring 4 by fixing bolts 6; the fixing plate 5 is in contact with the drill bit outer ring 4; a reaming plate 7 is fixedly connected to the outer side wall of the fixing plate 5; multiple first drill teeth 8 are fixedly connected to the side wall of the reaming plate 7, and the first drill teeth... 8 is set on the side wall of the reaming plate 7 corresponding to the rotation direction of the drill rod 1; multiple second drill teeth 9 are fixedly connected to the bottom positions of the conical drill bit 2 and the support rod 3; during operation, when it is necessary to construct the pile pit, a reverse circulation drilling rig is selected for drilling, which has good hole quality, fast speed and low cost. When the reverse circulation drilling rig is working, the coupling drives the high-speed rotation of the reducer, which drives the low-speed shaft to rotate. The low-speed shaft can be connected to the top of the drill rod 1 through a flange, and then drives the drill rod 1 and the conical drill bit 2 to rotate through the flange to complete the cutting drilling work. Mud is injected between the drill rod 1 and the conical drill bit 2. The excavated soil and debris are quickly discharged from the drill rod 1 to the ground and treated in the mud sedimentation tank for recycling. Before the construction of the expanded support pile, three fixing plates 5 are installed on the outer wall of the drill bit outer ring 4 using fixing bolts 6. Each fixing plate 5 is fixed to the drill bit outer ring 4 with four fixing bolts 6. The first drill tooth 8 is welded to the side wall of the expansion plate 7 fixed on the fixing plate 5, thus forming a drill bit with a larger pile diameter, such as a 1.6-1.2m expanded support pile drill bit. Three expansion plates 7 are added around the outer ring 4 of the original 1.2m drill bit. The expansion plates 7 can be made of wear-resistant steel plate with a thickness of 4. The first drill bit 8, which is installed in cm, is made of the same material as the second drill bit 9. The modified drill bit is suitable for 1.6m expanded support piles. First, the expansion plate 7 is installed on the outer wall of the outer ring 4 of the drill bit to form a 1.6m drill bit. The pile pit is then excavated. After the excavation is completed and the inspection is passed, the drill bit is lifted to the hole. The operator removes the three expansion plates 7. The diameter of the drill bit after removal is 1.2m. Then it is re-inserted into the hole to continue drilling into the reduced diameter pile pit. This reduces the steps of moving the machine and changing the drill bit, making the construction of the reduced diameter pile pit more convenient and effectively saving manpower and resources.

[0031] like Figures 3 to 6As shown, a plug block 10 is fixedly connected to the top of the second drill bit 9; a fixing protrusion 901 is slidably connected inside the support rod 3; an anti-dislodgement block 902 is fixedly connected to the side wall of the fixing protrusion 901; the anti-dislodgement block 902 is slidably connected inside the support rod 3; a spring is fixedly connected between the fixing protrusion 901 and the side wall of the support rod 3; a groove is provided on the side wall of the plug block 10 at the position corresponding to the fixing protrusion 901; during operation, when the second drill bit 9 needs to be replaced during the use of the drill bit, the second drill bit 9 can be removed and replaced. During the rotation of the drill bit, the fixing protrusion 901 engages with the groove on the side wall of the plug block 10, which increases the friction between the plug block 10 and the support rod 3, thereby making the second drill bit 9 more resistant to resistance. In this configuration, stability can be better maintained, and the distribution of the fixing protrusions 901 can be adjusted. Specifically, the fixing protrusions 901 facing the rotation direction of the second drill tooth 9 are positioned away from the second drill tooth 9 on the insert block 10, while the fixing protrusions 901 facing away from the rotation direction of the second drill tooth 9 are positioned close to the second drill tooth 9 on the insert block 10. This increases the friction between the fixing protrusions 901 and the insert block 10 when the second drill tooth 9 is obstructed and deflected, thus improving the support effect of the fixing protrusions 901 on the insert block 10. At the same time, during the sliding process of the fixing protrusions 901, the anti-detachment block 902 makes the sliding of the fixing protrusions 901 more stable and also blocks the fixing protrusions 901, effectively preventing the fixing protrusions 901 from detaching from the support rod 3.

[0032] like Figures 3 to 4 As shown, a guide plate 11 is provided at the bottom of the drill rod 1; the bottom of the guide plate 11 is inclined, with the highest point near the outer side of the drill rod 1 and the lowest point away from the outer side of the drill rod 1; during operation, as the drill bit digs downward, the conical shape of the guide plate 11 can position the descent of the drill bit, thereby reducing the tilting of the drill bit and making the digging direction of the drill bit more accurate.

[0033] like Figures 3 to 4 As shown, an air duct 12 connects the slot of the insert 10 to the sliding cavity of the guide plate 11; multiple springs are fixed between the top of the guide plate 11 and the drill rod 1; during operation, when the drill bit is not in use, the second drill tooth 9 can be removed, and the spring force will pull the guide plate 11 back into the drill rod 1, avoiding damage to the guide plate 11. When the drill bit needs to be used, the insert 10 of the second drill tooth 9 can be inserted into the support rod 3, and the insert 10 can push the air inside the slot into the sliding cavity of the guide plate 11 through the air duct 12, thereby allowing the guide plate 11 to be pushed downward, thus guiding the descent of the drill rod 1.

[0034] like Figure 2 and Figure 7 As shown, a support ring 13 is fixedly connected to the outer wall of the drill rod 1; a connecting cable 14 is fixedly connected between the fixing nut corresponding to the fixing bolt 6 and the support ring 13; a support plate 601 is fixedly connected to the side wall of the nut of the fixing bolt 6 by a spring; the support plate 601 is set at the position corresponding to the screw of the fixing bolt 6; during operation, when it is necessary to fix the fixing plate 5 by the cooperation of the fixing bolt 6 and the nut, the fixing bolt 6 can be inserted into the screw hole opened on the fixing plate 5 and the drill rod 1, and then the fixing bolt 6 is first rotated several turns in the opposite direction of the rotation of the nut. After the rotation is completed, the nut is screwed into the fixing bolt 6. The fixing bolt 6 is used for fixing, and the length of the connecting cable 14 can be adjusted according to actual needs. After the fixing bolt 6 is fixed with a nut, the pulling of the connecting cable 14 increases the pressure between the threads of the nut and the fixing bolt 6, thereby increasing the friction between the nut and the fixing bolt 6. At the same time, during the process of screwing the nut into the fixing bolt 6, the support plate 601 contacts the outer wall of the fixing plate 5, which continuously compresses the spring between the nut and the support plate 601. Through the elastic force of the spring, the pressure between the nut and the fixing bolt 6 is increased, thereby improving the fixing effect of the fixing bolt 6 on the fixing plate 5.

[0035] like Figure 4 As shown, a positioning rod 15 is fixedly connected inside the sliding cavity of the guide plate 11; the positioning rod 15 is slidably connected inside the guide plate 11; the positioning rod 15 is arranged parallel to the sliding direction of the guide plate 11; during operation, when the guide plate 11 is sliding, the positioning rod 15 restricts the guide plate 11, which can reduce the tilting of the guide plate 11 during the sliding process, and make the guide plate 11 more stable during the sliding process.

[0036] like Figure 4 As shown, a blocking block 16 is fixedly connected to the end of the positioning rod 15; a sliding cavity is provided at the corresponding position inside the guide plate 11; during operation, when the positioning rod 15 positions the sliding of the guide plate 11, the blocking block 16 can block the guide plate 11 after it slides outward, which can effectively prevent the guide plate 11 from falling out of the drill rod 1.

[0037] like Figure 1As shown, a threaded plate 17 is fixedly connected to the side wall of the drill rod 1; the threaded plate 17 is located near the top of the outer ring 4 of the drill bit on the drill rod 1; multiple slots are formed on the threaded plate 17; during operation, when the drill rod 1 rotates and continuously digs into the pile pit, the threaded plate 17, with its thread shape, allows the drill rod 1 to exert greater pressure on the soil as it digs downwards, thus increasing the force of the drill rod 1 during digging and improving the digging effect. Simultaneously, the slots on the threaded plate 17 allow the drill rod 1 to rotate at a relatively high speed as it digs downwards, causing the soil to pass through the slots due to inertia. Therefore, the slots have less impact on the rotation of the drill rod 1. When the drill rod 1 is lifted upwards, the slots further reduce the obstruction of the soil against the threaded plate 17, effectively preventing the threaded plate 17 from affecting the lifting of the drill rod 1.

[0038] like Figure 6 As shown, a rubber sheet 18 is fixedly attached to the side wall of the insertion block 10; the rubber sheet 18 is disposed on the side wall of each insertion block 10 that contacts the slot; during operation, when the insertion block 10 is inserted into the slot, by providing the rubber sheet 18 on the side wall of the insertion block 10, the insertion block 10 can be inserted into the slot, and the effect of squeezing and pushing the air inside the slot is better, avoiding gas leakage. At the same time, by providing the rubber sheet 18 on the side wall of the insertion block 10, the contact area between the fixing protrusion 901 and the insertion block 10 is larger, thereby making the fixing protrusion 901 fix the insertion block 10 better.

[0039] like Figure 4 As shown, a ball bearing 19 is connected to the inside of the blocking block 16; the side wall of the ball bearing 19 contacts the side wall of the sliding cavity of the blocking block 16; during operation, when the blocking block 16 positions the guide plate 11, the rolling of the ball bearing 19 can change the sliding friction between the guide plate 11 and the blocking block 16 into rolling friction, thereby reducing the friction between the guide plate 11 and the blocking block 16 and reducing the wear between the guide plate 11 and the blocking block 16.

[0040] When constructing pile pits, a reverse circulation drilling rig is used. This method offers high-quality, fast, and low-cost drilling. During operation, the coupling drives the high-speed rotation of the reducer, which in turn drives the low-speed power shaft. This low-speed shaft is connected to the top of the drill rod 1 via a flange, which in turn drives the drill rod 1 and the conical drill bit 2 to rotate, completing the cutting and drilling process. Mud is injected between the drill rod 1 and the conical drill bit 2. The mud, along with the excavated soil and other debris, is quickly discharged from the drill rod 1 to the ground and treated in a mud sedimentation tank for recycling. Before constructing the expanded support pile, three fixing plates 5 are installed on the outer wall of the drill bit's outer ring 4 using fixing bolts 6. Each fixing plate 5 is secured to the drill bit's outer ring 4 with four fixing bolts 6. The first drill tooth 8 is welded to the side wall of the reaming plate 7, which is fixed to the fixing plate 5. This allows for the creation of drill bits with larger pile diameters, such as 1.6-1.2m drill bits for expanded and reinforced piles. Three reaming plates 7 are added around the outer ring 4 of the original 1.2m drill bit. The reaming plates 7 can be made of wear-resistant steel plates, 4cm thick. The first drill tooth 8 is made of the same material as the second drill tooth 9. The modified drill bit is then suitable for 1.6m expanded and reinforced piles. First, the reaming plates 7 are installed on the outer wall of the outer ring 4 of the drill bit to form a 1.6m drill bit. The pile pit is then excavated. After excavation is completed and inspection is passed, the drill bit is lifted to the borehole opening. The operator removes the three reaming plates 7, resulting in a 1.2m diameter drill bit. The drill bit is then re-inserted into the hole to continue drilling into the reduced-diameter pile pit. This reduces the need to move the machine and change the drill bit, making the construction of the reduced-diameter pile pit more convenient and effectively saving manpower and resources.

[0041] During the use of the drill bit, when it is necessary to replace the second drill tooth 9, the second drill tooth 9 can be removed and replaced. During the rotation of the drill bit, the engagement between the fixing protrusion 901 and the groove on the side wall of the insert block 10 increases the friction between the insert block 10 and the support rod 3, thereby allowing the second drill tooth 9 to maintain stability better when subjected to resistance. At the same time, the distribution position of the fixing protrusion 901 can be adjusted, that is, the fixing protrusion 901 facing the rotation direction of the second drill tooth 9 can be set at a position on the insert block 10 away from the second drill tooth 9. The fixing protrusion 901, located opposite to the rotation direction of the second drill tooth 9, is positioned on the insert block 10 near the second drill tooth 9. This increases the friction between the fixing protrusion 901 and the insert block 10 when the second drill tooth 9 is obstructed and deflected, thus improving the support effect of the fixing protrusion 901 on the insert block 10. Simultaneously, during the sliding process of the fixing protrusion 901, the anti-disengagement block 902 makes the sliding of the fixing protrusion 901 more stable and also blocks the fixing protrusion 901, effectively preventing the fixing protrusion 901 from disengaging from the support rod 3.

[0042] During the downward drilling process, the cone-shaped setting of the guide plate 11 can position the descent of the drill bit, thereby reducing the tilting of the drill bit and making the drilling direction more accurate.

[0043] When the drill bit is not in use, the second drill tooth 9 can be removed. At the same time, the spring force will pull the guide plate 11 back and retract it into the drill rod 1, avoiding the possibility of damage to the guide plate 11. When the drill bit needs to be used, the insert 10 of the second drill tooth 9 can be inserted into the support rod 3. The insert 10 can then push the air inside the slot into the sliding cavity of the guide plate 11 through the air duct 12, thereby allowing the guide plate 11 to be pushed downward, thus enabling the guide plate 11 to guide the descent of the drill rod 1.

[0044] When it is necessary to fix the fixing plate 5 by using the fixing bolt 6 and nut to cooperate, the fixing bolt 6 can be inserted into the screw hole opened on the fixing plate 5 and the drill rod 1. Then, first rotate the fixing bolt 6 several turns in the opposite direction of the rotation of the nut. After rotation, screw the nut into the fixing bolt 6 to fix the fixing bolt 6. The length of the connecting cable 14 can be adjusted according to actual needs. After fixing the fixing bolt 6 with the nut, the pulling of the connecting cable 14 can increase the pressure between the threads of the nut and the fixing bolt 6, thereby increasing the friction between the nut and the fixing bolt 6. At the same time, during the process of screwing the nut into the fixing bolt 6, the support plate 601 contacts the outer wall of the fixing plate 5, which will continuously compress the spring between the nut and the support plate 601. Through the elastic force of the spring, the pressure between the nut and the fixing bolt 6 can be increased, thereby making the fixing bolt 6 fix the fixing plate 5 better.

[0045] As the guide plate 11 slides, the positioning rod 15 restricts the guide plate 11, which reduces the tilting of the guide plate 11 and makes the guide plate 11 more stable during the sliding process.

[0046] When the positioning rod 15 positions the guide plate 11, the blocking block 16 can block the guide plate 11 after it slides outward, which can effectively prevent the guide plate 11 from falling out of the drill rod 1.

[0047] As drill rod 1 rotates and continuously excavates into the pit, the threaded plate 17 increases the pressure between drill rod 1 and the soil as it excavates downwards, resulting in greater force and better excavation performance. Furthermore, the slots on the threaded plate 17 allow the soil to pass through them due to inertia as drill rod 1 rotates rapidly downwards, minimizing their impact on the rotation of drill rod 1. Conversely, the slots also reduce soil resistance when lifting drill rod 1 upwards, effectively preventing the threaded plate 17 from hindering the lifting process.

[0048] After the insert 10 is inserted into the slot, the rubber sheet 18 on the side wall of the insert 10 allows the insert 10 to be inserted into the slot, which can better compress and push the air inside the slot and prevent gas leakage. At the same time, the rubber sheet 18 on the side wall of the insert 10 can increase the contact area between the fixing protrusion 901 and the insert 10, thereby making the fixing protrusion 901 fix the insert 10 better.

[0049] When the blocking block 16 positions the guide plate 11, the rolling of the ball 19 can change the sliding friction between the guide plate 11 and the blocking block 16 into rolling friction, thereby reducing the friction between the guide plate 11 and the blocking block 16 and reducing the wear between them.

[0050] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A detachable reducing drill bit, characterized in that: The system includes a drill rod (1); a tapered drill bit (2) is fixedly connected to the bottom of the drill rod (1); multiple support rods (3) arranged in a circular array are provided on the side wall of the drill rod (1); the ends of the support rods (3) are all fixedly connected to the outer ring of the drill bit (4); the outer ring of the drill bit (4) is concentrically arranged with the drill rod (1); a fixing plate (5) is fixedly connected to the outer wall of the outer ring of the drill bit (4) by fixing bolts (6); the fixing plate (5) is in contact with the outer ring of the drill bit (4); a reaming plate (7) is fixedly connected to the outer wall of the fixing plate (5); multiple first drill teeth (8) are fixedly connected to the side wall of the reaming plate (7), and the first drill teeth (8) are set on the side wall of the reaming plate (7) corresponding to the rotation direction of the drill rod (1); multiple second drill teeth (9) are fixedly connected to the bottom positions of the tapered drill bit (2) and the support rods (3). The top of the second drill bit (9) is fixedly connected to a plug (10); a fixing protrusion (901) is slidably connected inside the support rod (3); an anti-detachment block (902) is fixedly connected to the side wall of the fixing protrusion (901); the anti-detachment block (902) is slidably connected inside the support rod (3); a spring is fixedly connected between the fixing protrusion (901) and the side wall of the support rod (3); a groove is provided on the side wall of the plug (10) at the position corresponding to the fixing protrusion (901); A guide plate (11) is provided at the bottom of the drill rod (1); the bottom of the guide plate (11) is inclined, with the highest point near the outside of the drill rod (1) and the lowest point away from the outside of the drill rod (1). A vent pipe (12) is connected between the slot of the insert (10) and the sliding cavity of the guide plate (11); multiple springs are fixed between the top of the guide plate (11) and the drill rod (1); a fixed protrusion (901) facing the rotation direction of the second drill tooth (9) is set at a position away from the second drill tooth (9) on the insert (10), and a fixed protrusion (901) facing away from the rotation direction of the second drill tooth (9) is set at a position close to the second drill tooth (9) on the insert (10).

2. The detachable reducing drill bit according to claim 1, characterized in that: A support ring (13) is fixed to the outer wall of the drill rod (1); a connecting cable (14) is fixed between the fixing nut corresponding to the fixing bolt (6) and the support ring (13); a support plate (601) is fixed to the side wall of the nut of the fixing bolt (6) by a spring; the support plate (601) is set at the position of the screw of the corresponding fixing bolt (6).

3. A detachable reducing drill bit according to claim 1, characterized in that: A positioning rod (15) is fixedly connected inside the sliding cavity of the guide plate (11); the positioning rod (15) is slidably connected inside the guide plate (11); the sliding direction of the positioning rod (15) is parallel to that of the guide plate (11).

4. A detachable reducing drill bit according to claim 3, characterized in that: The end of the positioning rod (15) is fixed with a blocking block (16); a sliding cavity is provided at the corresponding position inside the guide plate (11).

5. A detachable reducing drill bit according to claim 2, characterized in that: A threaded plate (17) is fixed to the side wall of the drill rod (1); the threaded plate (17) is located on the drill rod (1) near the top of the outer ring (4) of the drill bit; the threaded plate (17) has multiple slots.

6. A detachable reducing drill bit according to claim 1, characterized in that: A rubber sheet (18) is fixed to the side wall of the insert (10); the rubber sheet (18) is disposed on the side wall of each insert (10) that contacts the slot.

7. A detachable reducing drill bit according to claim 4, characterized in that: The blocking block (16) is internally connected to a ball (19); the sidewall of the ball (19) is in contact with the sidewall of the sliding cavity of the blocking block (16).

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