Combined down-the-hole drill bit capable of drilling and chambering

Abstract

The invention discloses a combined down-the-hole drill bit capable of drilling and chambering. The combined down-the-hole drill bit is composed of a tool rest 1, a tool bit 2 and a locking and clamping device 3. The drill bit is installed on the down-the-hole drill, the drill bit locking and clamping device 3 is in the state of locking the tool bit 2, the drill bit has the same function as a common down-the-hole drill bit, a drill rod rotates while drilling in the drilling process, and a round hole 4 is formed in rock or concrete. When the drilling depth reaches the designed depth, the drilling machine is controlled to only drill without rotating, at the moment, the drill bit forms a rectangular pit 41 at the bottom of the hole, and steps 42 are formed on the two sides of the long edge of the rectangular pit. Drilling continues, a trigger bottom cap 321 at the bottom of the drill bit is extruded by a hole bottom step 42, the locking and clamping device 3 is unlocked, and the drill bit tool bit 2 can be unfolded after unlocking. After the machine is stopped and the drill rod is lifted, the drill rod is rotated by an angle, so that the bottom of the tool bit 2 falls on a rectangular hole step 42, a drilling machine is started to only drill without rotating, the drill rod is manually controlled to rotate, and the process is repeated until the step 42 is chiseled away by the tool bit, and then normal drilling operation is carried out. And continuously drilling to form a reaming section to the designed length.

Description

Technical Field

[0001] This invention relates to the field of drilling and reaming with down-the-hole drills, and specifically to a combined down-the-hole drill bit capable of both drilling and reaming. Background Technology

[0002] Rock anchors are needed and used in many fields. The construction of anchoring holes for rock anchors typically involves drilling straight holes with a drilling rig. To improve the reliability of the anchoring and its pull-out resistance, the straight hole is drilled first, then a reaming drill bit is used to enlarge the hole at the bottom before installing the matching reamed-hole anchor. Rock anchor holes are often very deep, reaching tens of meters in depth. Multiple extension rods are needed to lengthen the drill rods. The existing drilling rigs have a cumbersome process for changing reaming drill bits, which seriously delays the construction progress. For high slope support or excavation of caverns prone to rock bursts, where the anchor needs to be installed in the shortest possible time and immediately provide anchoring force, this method is insufficient to meet project requirements. Summary of the Invention

[0003] The purpose of this invention is to design a combined down-the-hole drill bit capable of drilling and reaming when installing underreamed anchor bolts using a down-the-hole drill rig. This drill bit can directly perform the reaming process after drilling a straight hole, eliminating the need to remove the drill rod and replace it with a reaming drill bit, thus saving anchor bolt hole-forming time and improving construction efficiency. Because a matching underreamed anchor bolt is used, the enlarged head of the anchor bolt engages with the reamed hole at the bottom of the hole, providing rapid anchoring force.

[0004] This invention discloses a combined down-the-hole drill bit capable of drilling and reaming, comprising a tool holder 1, a tool head 2, and a locking device 3. This drill bit can be mounted on a down-the-hole drilling machine for reinforcement and anchoring of rock or concrete underreaming anchor bolts.

[0005] Install the corresponding type of drill bit on a down-the-hole drill rig. First, lock the drill bit locking device 3 in the locked position of the cutter head 2. Since the cutter head 2 and the tool holder 1 are an integral unit, the function of the drill bit is the same as that of a regular down-the-hole drill bit. During drilling, the drill rod rotates while drilling, forming a circular hole 4 in the rock or concrete. When the hole reaches the designed depth, control the drill rig to only drill and not rotate. At this time, the drill bit forms a rectangular pit 41 at the bottom of the hole, and steps 42 are formed on both sides of the long side of the rectangular pit. Continue drilling. The trigger cap 321 at the bottom of the drill bit is pressed by the steps 42 at the bottom of the hole, which unlocks the locking device 3. After unlocking, the drill bit 2 can be unfolded. Stop the machine, lift the drill rod, and rotate it at an angle so that the bottom of the cutter head 2 rests on the rectangular hole steps 42. Start the drill rig to only drill and not rotate. Manually control the rotation of the drill rod. Repeat the above process until the cutter head removes the steps 42 before resuming normal drilling operations. Since the bottom of the cutter head 2 is a slope 23, when the cutter head drills downwards, the slope 23 at the bottom of the cutter head 2 causes the cutter head 2 to gradually be forced outwards until the cutter head 2 is limited, forming an enlarged drill bit, and continuing to drill forms an enlarged hole section to the designed length. Attached Figure Description

[0006] Figure 1This is a schematic diagram of the combined down-the-hole drill bit that can drill and enlarge holes, as disclosed in this invention.

[0007] Figure 2 This is a schematic diagram of the tool holder disclosed in this invention.

[0008] Figure 3 This is a schematic diagram of the blade head disclosed in this invention.

[0009] Figure 4 This is a schematic diagram of the tool holder pad disclosed in this invention.

[0010] Figure 5 This is a schematic diagram of the rotating locking pin disclosed in this invention.

[0011] Figure 6 This is a schematic diagram of the trigger disclosed in this invention.

[0012] Figure 7 This is a schematic diagram of the circular pin disclosed in this invention.

[0013] Figure 8 This is a schematic diagram of the unlocking process of the card locking device disclosed in this invention. Detailed Implementation

[0014] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. The embodiments described herein are only a part of the embodiments of the present invention, and not all of the 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.

[0015] The invention will be further described below with reference to the accompanying drawings. The invention discloses a combined down-the-hole drill bit capable of drilling and reaming, comprising a tool holder 1, a tool head 2, and a locking device 3. This drill bit can be mounted on a down-the-hole drilling machine for reinforcement and anchoring of rock or concrete underreaming anchor bolts.

[0016] The tool holder 1 is machined from a section of round steel bar. One end is machined into a structure that connects to the down-the-hole drill impactor, and the other end is slotted into two tuning fork-shaped forks 11.

[0017] The cutter head 2 consists of two pieces, machined from two steel plates of the same thickness. The thickness of the steel plates is half the width of the slot in the cutter holder 1. The two steel plates are stacked and inserted into the slot of the cutter holder, forming a cylindrical shape in the middle when joined with the tuning fork end 11 of the cutter holder. One end of the cutter head 2 is machined into an arc 21, with a pivot pin hole 22 at the center of the arc. The other end of the cutter head 2 is cut into a bevel 23.

[0018] A steel tool holder pad 12 is installed inside the tool holder slot 13. The width of the tool holder pad 12 is the same as the width of the tool holder slot 13, and the length is the same as the diameter of the round steel bar of the tool holder. The bottom of the tool holder pad 12 is machined into an arc-shaped groove 121, which matches the arc 21 of the tool head. Limiting surfaces 123 are provided at both ends of the tool holder pad. The tool holder pad 12 is installed and fixed at the root of the tool holder slot 13. The two tool heads 2 are inserted into the tool holder slot 13. A round shaft pin 26 is provided at the round shaft pin hole 22 corresponding to the tool head 2 to form the tool holder 1 and the tool head 2 as one unit. The two tool heads can swing around the pin 26 within the tool holder slot 13.

[0019] The two forks 11 of the tool holder 1 have slots 14 at their ends, and the cutter head 2 has a recessed hole 24 in the middle, with a locking pin 31 inside to form a locking device 3 between the tool holder 1 and the cutter head 2. The locking device 3 consists of a rotating locking pin 31, a trigger 32, a spring 33, a tension spring 34, etc. Figure 1 As shown in the AA cross-sectional view, when the rotating locking pin 31 engages with the cutter head recess 24, the cutter head 2 is locked to the cutter holder 1, and the cutter head 2 cannot swing. Figure 1 As shown in the BB cross-sectional view, when the trigger bottom cap 321 is compressed, the spring 33 is compressed, the trigger 32 rises, and the rotating pin 31 can rotate around the rotating shaft 312 under the action of the tension spring 34. The rotating pin 31 exits from the cutter head recess 24, the cutter holder 1 and the cutter head 2 are unlocked, and the cutter head 2 can swing around the round shaft pin 26 in the cutter holder 1. The trigger top cap 322 is engaged in the top cap groove 311 of the rotating pin 31. Due to the restriction of the inclined surface 123 on the cutter holder pad 12 installed on the cutter holder 1, the swing amplitude of the cutter head 2 is limited to a certain angle range, ensuring that the two inclined surfaces 23 do not separate after the two cutter heads 2 are unfolded.

[0020] The exhaust channel 16 of the tool holder 1, the exhaust channel 122 of the tool holder pad 12 and the exhaust channel 25 of the tool head 2 are connected, so that the compressed air discharged from the down-the-hole drill impactor is discharged from the bottom end 23 of the tool holder. The bottom end 23 of the tool holder is equipped with alloy teeth 27.

[0021] Install the corresponding model of drill bit onto the down-the-hole drill rig. First, lock the drill bit locking device 3 in the locked position of the cutter head 2. Since the cutter head 2 and the tool holder 1 are an integral unit, the function of the drill bit is the same as that of an ordinary down-the-hole drill bit, drilling a straight hole to the designed depth. Figure 8 As shown in Figure A, during drilling, the impactor hammers the drill bit, and the alloy teeth 27 of the drill bit impact the rock or concrete, turning it into powder. This powder is blown out by the discharged compressed air. The drill rod rotates as it drills, forming a circular hole 4 within the rock or concrete. An extended drill rod is then used to drill the hole to the designed depth. Figure 8 As shown in Figure B, after drilling to the designed depth, the drilling rig is controlled to drill without rotating. At this point, the drill bit forms a rectangular pit 41 at the bottom of the hole, and steps 42 are formed on both sides of the long side of the rectangular pit. Figure 8As shown in Figure C, drilling continues. The trigger cap 321 at the bottom of the drill bit is pressed by the bottom step 42 of the hole, which unlocks the locking device 3. After unlocking, the drill bit 2 can be unfolded. After stopping the machine and lifting the drill rod, rotate it at an angle so that the bottom of the drill bit 2 rests on the rectangular hole step 42. Start the drilling machine and drill without rotating. Manually control the rotation of the drill rod and repeat the above process until the drill bit removes the step 42 before resuming normal drilling operations.

[0022] Because the bottom end of the drill bit 2 is a slope 23, when the drill bit is drilling downwards, the slope 23 at the bottom end of the drill bit 2 causes the drill bit 2 to gradually be forced outwards until the drill bit 2 is limited by the slope 123 of the tool holder pad, forming an enlarged drill bit. The two drill bits 2 are tightened by the tension spring 28 in the vent groove, keeping the two drill bits 2 in an open state. The drill bit continues to drill, forming an enlarged hole section to the designed length. When the drill rod is lifted, the open drill bit 2 is squeezed into the drill bit holder 1 by the straight hole wall 4 in the straight rod section, and the drill bit is pulled out of the hole. The drill bit 2 opens again. When the drill bit 2 is closed, the reset pin resets the trigger 32, and the next drilling and enlargement operation is performed.

[0023] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. However, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. This invention discloses a combined down-the-hole drill bit capable of drilling and enlarging holes, consisting of a tool holder 1, a tool head 2, and a locking device 3. The drill bit can be mounted on a down-the-hole drilling device for reinforcement and anchoring of rock or concrete under-hole anchor bolts.

2. The tool holder 1 as described in claim 1 is machined from a section of round steel bar, with one end machined into a structure connected to the down-the-hole drill impactor, and the other end slotted into two forks 11 in the shape of a tuning fork.

3. The cutter head 2 as described in claim 1 has two pieces, which are processed from two steel plates of the same thickness. The thickness of the steel plate is half the width of the slot of the cutter holder 1. After the two steel plates are stacked, they can be inserted into the slot of the cutter holder. When they are combined with the tuning fork end 11 of the cutter holder, they can form a cylindrical shape in the middle. One end of the cutter head 2 is processed into an arc 21, and a pivot pin hole 22 is provided at the center of the arc. The other end of the cutter head 2 is cut into a bevel 23.

4. As described in claim 1, a steel tool holder pad 12 is provided in the tool holder groove 13 of the tool holder 1. The width of the tool holder pad 12 is the same as the width of the tool holder groove 13, and the length is the same as the diameter of the round steel bar of the tool holder. The bottom of the tool holder pad 12 is machined into an arc-shaped groove 121, which matches the arc 21 of the tool head. Limiting surfaces 123 are provided at both ends of the tool holder pad. The tool holder pad 12 is installed and fixed at the root of the tool holder groove 13. The two tool heads 2 are inserted into the tool holder groove 13. A round shaft pin 26 is provided at the round shaft pin hole 22 corresponding to the tool head 2 to form the tool holder 1 and the tool head 2 as one unit. The two tool heads can swing around the pin 26 in the tool holder groove 13.

5. As described in claim 1, the two forks 11 of the tool holder 1 have slotted openings 14 at their ends, and the cutter head 2 has a recessed hole 24 in the middle, with a locking pin 31 inside to form a locking device 3 between the tool holder 1 and the cutter head 2.

6. The locking device 3 as described in claim 1 is composed of a rotating locking pin 31, a trigger 32, a spring 33, a tension spring 34, etc. When the rotating locking pin 31 is engaged in the cutter head recess 24, the cutter head 2 is locked to the cutter holder 1, and the cutter head 2 cannot swing. When the trigger bottom cap 321 is pressed, the spring 33 is compressed, the trigger 32 rises, and the rotating locking pin 31 can rotate around the rotating shaft 312 under the action of the tension spring 34. The rotating locking pin 31 exits from the cutter head recess 24, the cutter holder 1 and the cutter head 2 are unlocked, and the cutter head 2 can swing around the round shaft pin 26 in the cutter holder 1. The trigger top cap 322 is engaged in the top cap groove 311 of the rotating locking pin 31. Due to the restriction of the inclined surface 123 on the cutter holder pad 12 installed on the cutter holder 1, the swing amplitude of the cutter head 2 is limited to a certain angle range, ensuring that the two inclined surfaces 23 do not separate after the two cutter heads 2 are unfolded.

7. The exhaust channel 16 of the tool holder 1 as described in claim 1, wherein the exhaust channel 122 of the tool holder pad 12 and the exhaust channel 25 of the tool head 2 are connected, so that the compressed air discharged from the down-the-hole drill impactor from the tool holder is discharged from the bottom end 23 of the tool holder, and the bottom end 23 of the tool holder is equipped with alloy teeth 27.

8. The combined down-the-hole drill bit for drilling and reaming as described in claim 1, wherein drilling and reaming are achieved through the following steps: The first step is to install the corresponding model of drill bit on the down-the-hole drilling rig. First, lock the drill bit locking device 3 in the state of locking the cutter head 2, since the cutter head 2 and the tool holder 1 are a whole. The second step involves the impactor striking the drill bit during drilling. The alloy teeth 27 of the drill bit impact the rock or concrete into powder, which is then blown out by the compressed air. The drill rod rotates as it drills, forming a round hole 4 in the rock or concrete. The third step is to drill the hole to the designed depth by extending the drill rod in the middle. After the hole is drilled to the designed depth, the drill is controlled to only drill and not rotate. At this time, the drill bit forms a rectangular pit 41 at the bottom of the hole, and steps 42 are formed on both sides of the long side of the rectangular pit. Fourth step, continue drilling. The trigger cap 321 at the bottom of the drill bit is squeezed by the bottom step 42 of the hole, which unlocks the locking device 3. After unlocking, the drill bit 2 can be unfolded. Fifth step: After stopping the machine and lifting the drill rod, rotate it at an angle so that the bottom of the cutter head 2 rests on the rectangular hole step 42. Start the drilling machine and drill without rotating. Manually control the rotation of the drill rod. Repeat the above process until the cutter head removes the step 42 before proceeding with normal drilling operations. Step 6: Since the bottom end of the cutter head 2 is a slope 23, when the cutter head drills downwards, the slope 23 at the bottom end of the cutter head 2 causes the cutter head 2 to gradually be forced outwards until the cutter head 2 is limited by the slope 123 of the tool holder pad, forming an enlarged drill bit. The two cutter heads 2 are tightened by the tension spring 28 in the air groove, keeping the two cutter heads 2 in an open state. The cutter head continues to drill in to form an enlarged hole section to the designed length. Step 7: When the drill rod is lifted, the open cutter head 2 is squeezed into the drill bit holder 1 by the straight hole wall 4 in the straight rod section. The drill bit is pulled out of the hole, and the cutter head 2 opens again. When the cutter head 2 is closed, the reset pin is used to reset the trigger 32 to start the next drilling and reaming operation.

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