Lightweight high-strength electric hammer drill and preparation process thereof

Abstract

The invention discloses a lightweight high-strength electric hammer drill and a preparation process thereof, and belongs to the technical field of electric hammer drills. The light-weight high-strength electric hammer drill comprises an electric hammer drilling machine and an electric hammer drill bit body, a cutting tool bit is installed at the front end of the electric hammer drill bit body, a carbon fiber composite rod is arranged in a hollow drill rod, and a penetrating rod is installed between the carbon fiber composite rod and the electric hammer drill bit body. The electric hammer drill bit solves the problems that in the actual using process of an existing drill bit body, the weight of the drill bit affects operation, and the working life of the drill bit cannot be guaranteed in long-term work, by introducing the ceramic tool bit, the wear-resisting life of the electric hammer drill bit body is increased by the order of magnitude, and when the ceramic tool bit drills reinforced concrete, the service life of the electric hammer drill bit body is prolonged. The electric hammer drill bit is high in abrasion resistance, the three-dimensional woven carbon fiber structure is adopted, the pulse impact load of an electric hammer can be effectively resisted, and the electric hammer drill bit body is not prone to layering and cracking under high-frequency impact and excellent in toughness performance.

Description

Technical Field

[0001] This invention relates to the field of electric hammer drill technology, specifically to a lightweight, high-strength electric hammer drill and its manufacturing process. Background Technology

[0002] A hammer drill converts the rotational torque of an electric motor into the reciprocating motion of a piston through mechanisms such as a cam and crankshaft, thereby impacting the drill bit to achieve a striking effect while the drill bit continues to rotate. Compared to an impact drill, a hammer drill vibrates less, typically has a power output of 13.5 amps or higher, and uses a special square or round head drill shank with a chuck to prevent loosening. The drill bit is usually made of metal, and the bottom arc surface has a sharp angle design, which is beneficial for rock breaking but not for hole enlargement.

[0003] Chinese Patent CN210858588U discloses a lightweight discardable drill bit for rapid well construction in groundwater monitoring wells, comprising a drill bit body, a support platform, and a connector. The support platform is positioned between the drill bit body and the connector, and the center points of the drill bit body, support platform, and connector are on the same axis. The drill bit body, support platform, and connector are integrally molded. This patented discardable drill bit features a lightweight, integrally molded design, which facilitates hole enlargement, enhances drill bit stability, and meets the requirements of weight reduction, cost reduction, and mass production. It solves problems such as easy drill bit detachment, poor hole enlargement, limited pressure resistance during drilling, and the impact on drill bit stability due to minimal stress on the bottom of the drill bit.

[0004] In actual use, the weight of the drill bit body in the aforementioned patent affects operation, and its service life cannot be guaranteed during long-term operation; therefore, it does not meet the existing needs. In response, we propose a lightweight high-strength electric hammer drill and its manufacturing process. Summary of the Invention

[0005] The purpose of this invention is to provide a lightweight, high-strength electric hammer drill and its manufacturing process, which solves the problem mentioned in the background art that the weight of the drill bit affects operation during actual use and cannot guarantee the working life of the drill bit during long-term operation.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a lightweight high-strength electric hammer drill, comprising an electric hammer drill rig and an electric hammer drill bit body, wherein the electric hammer drill bit body is disposed at the front end of the electric hammer drill rig, and a cutting head is installed at the front end of the electric hammer drill bit body; a hollow drill rod is installed at the rear end of the electric hammer drill bit body; the hollow drill rod extends into the electric hammer drill rig and is fixedly connected to the electric hammer drill rig by a locking component; a carbon fiber composite rod is disposed inside the hollow drill rod; and a through rod is installed between the carbon fiber composite rod and the electric hammer drill bit body.

[0007] Preferably, the surface of the main body of the electric hammer drill bit is provided with an integrally formed helical groove. The pitch and depth of the helical groove vary along the length of the drill rod. The groove depth of the chip removal inlet section of the helical groove is shallower than the groove depth of the chip removal middle section, the groove depth of the chip removal middle section of the helical groove is shallower than the groove depth of the chip removal outlet section, the pitch of the chip removal inlet section of the helical groove is smaller than the pitch of the chip removal middle section, and the pitch of the chip removal middle section of the helical groove is smaller than the pitch of the chip removal outlet section.

[0008] Preferably, the front end of the hammer drill bit body is provided with an integrally formed locking groove, and the rear end of the cutting head is provided with an integrally formed tapered barb. The tapered barb is embedded in the locking groove and fitted into the hammer drill bit body. The rear end of the cutting head is provided with a fastening mounting groove, and the inner wall of the fastening mounting groove and the surface of the tapered barb are both provided with a wear-resistant layer.

[0009] Preferably, an integrally formed installation port is provided between the main body of the electric hammer drill bit and the hollow drill rod, and an integrally formed connection port is provided inside the hollow drill rod. The through rod passes through the connection port and abuts against the main body of the electric hammer drill bit and the hollow drill rod respectively.

[0010] Preferably, a locking screw is provided between the hollow drill rod and the main body of the electric hammer drill bit, and the locking screw is fixedly connected to the main body of the electric hammer drill bit and the hollow drill rod respectively by threads.

[0011] Preferably, the upper end of the cutting head is provided with an integrally formed ceramic cutting head, which is embedded inside the cutting head and fixedly connected to the cutting head by threads. The surface of the ceramic cutting head is provided with a composite coating, which is a combination of a TiAlN multilayer film and a DLC coating.

[0012] Preferably, a clamping block is installed between the hollow drill rod and the carbon fiber composite rod, the clamping block being in contact with both the hollow drill rod and the carbon fiber composite rod, and a buffer damping pad is provided inside the clamping block.

[0013] Preferably, the inner side of the carbon fiber composite rod is provided with an integrally formed weight-reducing through-hole, and the bottom end of the carbon fiber composite rod is fixedly connected to the through rod by threads.

[0014] A manufacturing process for a lightweight, high-strength electric hammer drill includes the following steps: Step 1: Use precision forging to obtain the blanks of the electric hammer drill bit body and the hollow drill rod, and forge the through rod, leaving machining allowance for the locking groove; Step 2: Using a CNC lathe and machining center, a locking groove for mechanical interlocking is machined. The roughness of the inner wall of the locking groove is controlled within Ra1.6. The junction of the electric hammer drill bit body and the hollow drill rod is precision machined to eliminate step difference, ensure a smooth transition of the drill rod outer diameter, and reduce stress concentration. Step 3: Using laser etching, micro-pits and grooves are processed on the mating surface of the hammer drill bit body, and the connection joint is shaped to enhance the anchoring effect of the connection. Step 4: Eliminate processing stress, refine grains, and prepare for subsequent heat treatment. Heat to 920℃ at a rate of 8-10℃ / s and hold for a period of time. Then, rapidly cool in a special quenching medium to obtain a high-hardness martensitic structure. Eliminate quenching stress and stabilize dimensions through stepped tempering. Finally, the body of the electric hammer drill bit maintains both high hardness and sufficient toughness. Step 5: Sandblast the mating surfaces of the locking groove and the mounting port; Step Six: Weave carbon fibers into a tubular preform. Compared with two-dimensional layup, the three-dimensional braided structure has better interlaminar shear strength and impact resistance. The woven carbon fiber preform is placed into a precision mold using a resin transfer molding process. Low-viscosity high-temperature resin is injected under vacuum negative pressure to ensure that the resin fully impregnates each fiber, thus producing a carbon fiber composite rod. For drill bits that are subjected to high-frequency impact, toughened modified epoxy resin or bismaleimide resin should be selected to ensure that they do not crack under severe vibration. Step 6: Place the impregnated mold into an autoclave and cure it in stages according to the resin curing curve. The temperature and time of the stages are from 120℃ for 1 hour to 160℃ for 2 hours, and then 180℃ for 2 hours. During the curing process, the pressure inside the tube is maintained by the built-in air bladder to ensure that the inner wall of the drill rod is smooth and flat and to ensure the accuracy of the inner diameter. Step 7: Degrease the mating surfaces of the installation port with acetone, and grind or plasma treat the connecting ends of the carbon fiber tube to remove the release agent and activate the surface, improve the connection strength, insert the through rod, lock the through rod with internal thread, and drive in the interference fit locking screw to fix the carbon fiber composite rod, hollow drill rod and electric hammer drill bit body. Step 8: Coat the taper barb of the ceramic cutter head with a TiAlN multilayer film and a DLC coating, and sinter at high temperature to form a brazable fastening groove surface. Assemble the metallized ceramic cutter head taper barb with the locking groove, place it in a vacuum furnace and heat to 800-950℃, hold for 10-30 minutes, and control the cooling rate to ≤5℃ / min to reduce thermal stress. Step 9: Assemble the connected and combined electric hammer drill bit body into the electric hammer drill machine to complete the preparation work.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The main body of the electric hammer drill bit of the present invention, by installing a carbon fiber composite rod at the connection position with the electric hammer drill, has a specific stiffness of 3-4 times that of steel. Under the same weight, the torsional stiffness of the carbon fiber drill rod is two to three times higher than that of the steel drill rod. Under the same stiffness, the weight can be reduced by 60%-70%. The torsional deformation of the drill rod during drilling is reduced, the torque transmission efficiency is higher, and the drilling is more stable and straighter. The three-dimensional woven carbon fiber structure has an interlayer shear strength that is more than 50% higher than that of two-dimensional layup, which can effectively resist the pulse impact load of the electric hammer. This makes the main body of the electric hammer drill bit less prone to delamination and cracking under high-frequency impact, and exhibits excellent toughness. Furthermore, through the spiral grooves on the surface of the main body of the electric hammer drill bit, the reflection and attenuation of the shock wave in the drill rod are reduced by stepping and stress wave matching optimization, and the impact energy is transmitted to the rock interface more efficiently. The drilling speed can be increased by 15%-20%, achieving a faster speed with the same energy.

[0016] 2. This invention, through the introduction of ceramic cutting tips, significantly improves the wear resistance of the main body of the hammer drill bit. Ceramic cutting tips exhibit extremely strong resistance to abrasive wear when drilling reinforced concrete, maintaining sharpness even after prolonged use and eliminating the need for frequent resharpening. Combined with TiAlN multilayer film and DLC coating, the coefficient of friction is reduced by 30%-40%, resulting in smoother chip removal and less cutting heat. Under the same working conditions, the total lifespan of the drill bit can reach 2-3 times that of traditional products. The tapered barb screws into the locking groove; when the central nut is rotated, it pushes the tapered barb inward, utilizing the principle of tapered surface engagement to tighten the main body of the hammer drill bit. The end of the main body ultimately presses against the bottom of the cutting tip, clearly defining the installation position and transmitting axial impact force. This robust and durable design extends the drill bit's lifespan, reduces replacement frequency, and, in the long run, results in lower overall operating costs compared to traditional drill bits. Attached Figure Description

[0017] Figure 1 This is an isometric view of the front view of the present invention; Figure 2 This is an isometric view of the main body of the electric hammer drill bit of the present invention from the side. Figure 3 This is an isometric view of the main body of the electric hammer drill bit of the present invention from the rear. Figure 4 This is an isometric view of the front view of the main body of the electric hammer drill bit of the present invention after disassembly; Figure 5 For the present invention Figure 4 Enlarged view of a portion of area A in the middle; Figure 6 This is an isometric view of the main body of the electric hammer drill bit of the present invention after disassembly. Figure 7 For the present invention Figure 6 A magnified view of a section in area B.

[0018] In the diagram: 1. Main body of the electric hammer drill bit; 101. Spiral groove; 102. Locking groove; 2. Cutting head; 201. Fastening mounting groove; 202. Ceramic cutting head; 203. Tapered barb; 3. Hollow drill rod; 301. Mounting port; 302. Connection port; 303. Through rod; 304. Locking screw; 305. Carbon fiber composite rod; 306. Clamping block; 307. Weight reduction port; 4. Electric hammer drill. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] To address the issue that the weight of existing drill bits affects operation and cannot guarantee their service life during long-term use, please refer to [the relevant documentation / reference]. Figure 1 - Figure 4 , Figure 6 - Figure 7 This embodiment provides the following technical solution: This embodiment of a lightweight, high-strength electric hammer drill includes an electric hammer drill 4 and an electric hammer drill bit body 1. The electric hammer drill bit body 1 is located at the front end of the electric hammer drill 4, and a cutting head 2 is installed at the front end of the electric hammer drill bit body 1. A hollow drill rod 3 is installed at the rear end of the electric hammer drill bit body 1. The hollow drill rod 3 extends into the electric hammer drill 4 and is fixedly connected to the electric hammer drill 4 by a locking component. A carbon fiber composite rod 305 is installed inside the hollow drill rod 3, and a through rod 303 is installed between the carbon fiber composite rod 305 and the electric hammer drill bit body 1. The electric hammer drill bit body 1 adopts a combined type. By installing the carbon fiber composite rod 305 at the connection position with the electric hammer drill 4, the specific stiffness of the carbon fiber composite material is 3-4 times that of steel. Under the same weight, the torsional stiffness of the carbon fiber drill rod is two to three times higher than that of the steel drill rod.

[0021] In addition, an integrally formed installation port 301 is provided between the main body 1 of the electric hammer drill bit and the hollow drill rod 3, and an integrally formed connection port 302 is provided inside the hollow drill rod 3. The through rod 303 passes through the connection port 302 and abuts against the main body 1 of the electric hammer drill bit and the hollow drill rod 3 respectively.

[0022] Furthermore, a clamping block 306 is installed between the hollow drill rod 3 and the carbon fiber composite rod 305. The clamping block 306 is in contact with both the hollow drill rod 3 and the carbon fiber composite rod 305. A buffer damping pad is provided inside the clamping block 306. The torsional stiffness of the carbon fiber drill rod is two to three times higher than that of the steel drill rod. Under the same stiffness, the weight can be reduced by 60% to 70%. The torsional deformation of the drill rod is reduced during drilling, the torque transmission efficiency is higher, and the drilling is more stable and straighter. The three-dimensional woven carbon fiber structure has an interlayer shear strength that is more than 50% higher than that of two-dimensional layup, which can effectively resist the pulse impact load of the electric hammer. The buffer damping pad helps maintain the positional stability between them during operation, thereby improving the work quality.

[0023] The inner side of the carbon fiber composite rod 305 is provided with an integrally formed weight-reducing through-hole 307. The bottom end of the carbon fiber composite rod 305 is fixedly connected to the through rod 303 by threads, which makes the main body 1 of the electric hammer drill bit less prone to delamination and cracking under high-frequency impact, and exhibits excellent toughness. Furthermore, through the spiral groove 101 on the surface of the electric hammer drill bit body 1, the step-like structure and stress wave matching optimization reduce the reflection and attenuation of shock waves in the drill rod, and the impact energy is transferred to the rock interface more efficiently, which can increase the drilling speed by 15%-20%, achieving a faster drilling speed with the same energy.

[0024] Specifically, the main body 1 of the combined electric hammer drill bit is equipped with a carbon fiber composite rod 305 installed at the connection position with the electric hammer drill 4. The specific stiffness of carbon fiber composite material is 3-4 times that of steel. Under the same weight, the torsional stiffness of the carbon fiber drill rod is two to three times higher than that of the steel drill rod. Under the same stiffness, the weight can be reduced by 60%-70%. The torsional deformation of the drill rod during drilling is reduced, the torque transmission efficiency is higher, and the drilling is more stable and straighter. The three-dimensional woven carbon fiber structure increases the interlayer shear strength by more than 50% compared with two-dimensional layup, which can effectively resist the pulse impact load of the electric hammer. This makes the main body 1 of the electric hammer drill bit less prone to delamination and cracking under high-frequency impact, and exhibits excellent toughness. Furthermore, the spiral groove 101 on the surface of the main body 1 of the electric hammer drill bit is optimized through step-like structure and stress wave matching to reduce the reflection and attenuation of shock waves in the drill rod. The impact energy is transferred to the rock interface more efficiently, and the drilling speed can be increased by 15%-20%, achieving a faster speed with the same energy.

[0025] To address the issue that the weight of existing drill bits affects operation and cannot guarantee their service life during long-term use, please refer to [the relevant documentation / reference]. Figure 1 - Figure 5 This embodiment provides the following technical solution: In this embodiment, the surface of the main body 1 of the electric hammer drill bit is provided with an integrally formed spiral groove 101. The pitch and groove depth of the spiral groove 101 vary along the length of the drill rod. The groove depth of the chip removal inlet section of the spiral groove 101 is shallower than the groove depth of the chip removal middle section, the groove depth of the chip removal middle section of the spiral groove 101 is shallower than the groove depth of the chip removal outlet section, the pitch of the chip removal inlet section of the spiral groove 101 is smaller than the pitch of the chip removal middle section, and the pitch of the chip removal middle section of the spiral groove 101 is smaller than the pitch of the chip removal outlet section.

[0026] The main body 1 of the electric hammer drill bit has an integrally formed locking groove 102 at its front end, and the rear end of the cutting head 2 has an integrally formed tapered barb 203. The tapered barb 203 is embedded in the locking groove 102 and fits into the main body 1 of the electric hammer drill bit. The rear end of the cutting head 2 has a fastening mounting groove 201. The inner wall of the fastening mounting groove 201 and the surface of the tapered barb 203 are both provided with wear-resistant layers. Under the same working conditions, the total life of the drill bit can reach 2-3 times that of traditional products. The tapered barb 203 is screwed into the locking groove 102. When the middle nut is rotated, it will push the tapered barb 203 to move inward. Using the principle of tapered surface engagement, the main body 1 of the electric hammer drill bit is held tighter and tighter.

[0027] In fact, a locking screw 304 is provided between the hollow drill rod 3 and the main body 1 of the electric hammer drill bit. The locking screw 304 is fixedly connected to the main body 1 of the electric hammer drill bit and the hollow drill rod 3 respectively through threads. The end of the main body 1 of the electric hammer drill bit finally presses against the bottom of the cutting head 2, which clarifies the installation position and transmits axial impact force. It is solid and durable, extends the life of the drill bit, reduces the replacement frequency, and in the long run, the overall cost of use is lower than that of traditional drill bits.

[0028] It should be noted that the upper end of the cutting head 2 is provided with an integrally formed ceramic cutting head 202. The ceramic cutting head 202 is embedded inside the cutting head 2 and is fixedly connected to the cutting head 2 by threads. The surface of the ceramic cutting head 202 is provided with a composite coating, which is a combination of TiAlN multilayer film and DLC coating. The introduction of the ceramic cutting head 202 increases the wear resistance of the main body 1 of the hammer drill by orders of magnitude. When drilling reinforced concrete, the ceramic cutting head 202 has extremely strong resistance to abrasive wear. After long-term use, the cutting edge remains sharp and does not require frequent resharpening. With the TiAlN multilayer film and DLC coating, the coefficient of friction is reduced by 30%-40%, chip removal is smoother, and cutting heat is less.

[0029] Specifically, the introduction of the ceramic cutter head 202 significantly improves the wear resistance of the main body 1 of the hammer drill bit. The ceramic cutter head 202 exhibits extremely strong resistance to abrasive wear when drilling reinforced concrete. After prolonged use, the cutting edge remains sharp, eliminating the need for frequent resharpening. Combined with the TiAlN multilayer film and DLC coating, the coefficient of friction is reduced by 30%-40%, resulting in smoother chip removal and less cutting heat. Under the same working conditions, the total lifespan of the drill bit can reach 2-3 times that of traditional products. The tapered barb 203 is screwed into the locking groove 102. When the middle nut is rotated, it pushes the tapered barb 203 inward. Utilizing the principle of tapered surface engagement, the main body 1 of the hammer drill bit is held tighter and tighter. Finally, the end of the main body 1 of the hammer drill bit rests against the bottom of the cutting head 2, clearly defining the installation position and transmitting axial impact force. This design ensures robustness and durability, extends the lifespan of the drill bit, reduces the frequency of replacement, and, in the long run, results in a lower overall operating cost compared to traditional drill bits.

[0030] A manufacturing process for a lightweight, high-strength electric hammer drill includes the following steps: Step 1: Using precision forging, the blanks of the electric hammer drill bit body 1 and the hollow drill rod 3 are obtained, and the through rod 303 is forged, leaving machining allowance for the locking groove 102. Step 2: Using a CNC lathe and machining center, a locking groove 102 for mechanical interlocking is machined. The roughness of the inner wall of the locking groove 102 is controlled within Ra1.6. Precision turning is performed at the junction of the electric hammer drill bit body 1 and the hollow drill rod 3 to eliminate step difference, ensure a smooth transition of the drill rod outer diameter, and reduce stress concentration. Step 3: Using laser etching, micro-pits and grooves are processed on the mating surface of the hammer drill bit body 1, and the connection port 302 is shaped to enhance the anchoring effect of the connection. Step 4: Eliminate processing stress, refine grains, and prepare for subsequent heat treatment. Heat to 920℃ at a rate of 8-10℃ / s and hold for a period of time. Then, rapidly cool in a special quenching medium to obtain a high-hardness martensitic structure. Eliminate quenching stress and stabilize dimensions through stepped tempering. Finally, ensure that the main body 1 of the electric hammer drill bit maintains both high hardness and sufficient toughness. Step 5: Sandblast the mating surfaces of the locking groove 102 and the mounting port 301; Step Six: The carbon fiber is woven into a tubular preform. Compared with two-dimensional layup, the three-dimensional woven structure has better interlaminar shear strength and impact damage resistance. The woven carbon fiber preform is placed into a precision mold using a resin transfer molding process. Low-viscosity high-temperature resin is injected under vacuum negative pressure to ensure that the resin fully wets each fiber, thus producing carbon fiber composite rod 305. For drill bits that are subjected to high-frequency impact, toughened modified epoxy resin or bismaleimide resin should be selected to ensure that they do not crack under severe vibration. Step 6: Place the impregnated mold into an autoclave and cure it in stages according to the resin curing curve. The temperature and time of the stages are from 120℃ for 1 hour to 160℃ for 2 hours, and then 180℃ for 2 hours. During the curing process, the pressure inside the tube is maintained by the built-in air bladder to ensure that the inner wall of the drill rod is smooth and flat and to ensure the accuracy of the inner diameter. Step 7: Degrease the mating surface of the installation port 301 with acetone, and grind or plasma treat the connecting end of the carbon fiber tube to remove the release agent and activate the surface to improve the connection strength. Insert the through rod 303, lock the through rod 303 with the internal thread, and drive in the interference fit locking screw 304 to fix the carbon fiber composite rod 305, the hollow drill rod 3, and the electric hammer drill bit body 1. Step 8: Coat the taper barb 203 of the ceramic cutter head 202 with a TiAlN multilayer film and a DLC coating, and sinter at high temperature to form a brazable fastening mounting groove 201 surface. Assemble the metallized ceramic cutter head 202 taper barb 203 with the locking groove 102, place it in a vacuum furnace and heat it to 800-950℃, hold it for 10-30 minutes, and control the cooling rate to ≤5℃ / min to reduce thermal stress. Step 9: Assemble the connected and assembled electric hammer drill bit body 1 into the electric hammer drill 4 to complete the preparation work.

[0031] Working Principle: During use, a carbon fiber composite rod 305 is installed at the connection point with the electric hammer drill 4. The specific stiffness of carbon fiber composite material is 3-4 times that of steel. Under the same weight, the torsional stiffness of the carbon fiber drill rod is two to three times higher than that of the steel drill rod. Under the same stiffness, the weight can be reduced by 60%-70%. The torsional deformation of the drill rod is reduced during drilling, the torque transmission efficiency is higher, and the drilling is more stable and straighter. The three-dimensional woven carbon fiber structure increases the interlaminar shear strength by more than 50% compared with two-dimensional layup, which can effectively resist the pulse impact load of the electric hammer. This makes the electric hammer drill bit body 1 less prone to delamination and cracking under high-frequency impact, and exhibits excellent toughness. The introduction of ceramic cutter head 202 increases the wear life of the electric hammer drill bit body 1 by orders of magnitude. When drilling reinforced concrete, the ceramic cutter head 202 has extremely strong resistance to abrasive wear, and the cutting edge remains sharp after long-term use. No frequent re-sharpening is required. With the addition of TiAlN multilayer film and DLC coating, the coefficient of friction is reduced by 30%-40%, resulting in smoother chip removal and less cutting heat. Under the same working conditions, the total lifespan of the drill bit can reach 2-3 times that of traditional products. The tapered barb 203 is screwed into the locking groove 102. When the middle nut is rotated, it pushes the tapered barb 203 inward. Utilizing the principle of tapered surface engagement, the main body 1 of the hammer drill bit is held tighter and tighter. Finally, the end of the main body 1 of the hammer drill bit is pressed against the bottom of the cutting head 2, which clarifies the installation position and transmits axial impact force. It is robust and durable. Furthermore, the spiral groove 101 on the surface of the main body 1 of the hammer drill bit is optimized through step-like structure and stress wave matching to reduce the reflection and attenuation of shock waves in the drill rod. The impact energy is transmitted to the rock interface more efficiently, and the drilling speed can be increased by 15%-20%, achieving faster speed with the same energy.

[0032] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A lightweight, high-strength electric hammer drill, comprising an electric hammer drill rig (4) and an electric hammer drill bit body (1), characterized in that, The main body (1) of the electric hammer drill bit is located at the front end of the electric hammer drill machine (4), and a cutting head (2) is installed at the front end of the main body (1). A hollow drill rod (3) is installed at the rear end of the main body (1). The hollow drill rod (3) extends into the electric hammer drill machine (4) and is fixedly connected to the electric hammer drill machine (4) by a locking component. A carbon fiber composite rod (305) is installed inside the hollow drill rod (3), and a through rod (303) is installed between the carbon fiber composite rod (305) and the main body (1).

2. The lightweight high-strength electric hammer drill according to claim 1, characterized in that, The surface of the main body (1) of the electric hammer drill bit is provided with an integrally formed spiral groove (101). The pitch and depth of the spiral groove (101) vary along the length of the drill rod. The groove depth of the chip removal inlet section of the spiral groove (101) is shallower than the groove depth of the chip removal middle section. The groove depth of the chip removal middle section of the spiral groove (101) is shallower than the groove depth of the chip removal outlet section. The pitch of the chip removal inlet section of the spiral groove (101) is smaller than the pitch of the chip removal middle section. The pitch of the chip removal middle section of the spiral groove (101) is smaller than the pitch of the chip removal outlet section.

3. The lightweight high-strength electric hammer drill according to claim 1, characterized in that, The front end of the hammer drill bit body (1) is provided with an integrally formed locking groove (102), and the rear end of the cutting head (2) is provided with an integrally formed tapered barb (203). The tapered barb (203) is embedded in the locking groove (102) and fitted into the hammer drill bit body (1). The rear end of the cutting head (2) is provided with a fastening mounting groove (201). The inner wall of the fastening mounting groove (201) and the surface of the tapered barb (203) are both provided with a wear-resistant layer.

4. A lightweight, high-strength electric hammer drill according to claim 1, characterized in that, An integrally formed installation port (301) is provided between the main body (1) of the electric hammer drill bit and the hollow drill rod (3). An integrally formed connection port (302) is provided inside the hollow drill rod (3). The through rod (303) passes through the connection port (302) and abuts against the main body (1) of the electric hammer drill bit and the hollow drill rod (3) respectively.

5. A lightweight, high-strength electric hammer drill according to claim 4, characterized in that, A locking screw (304) is provided between the hollow drill rod (3) and the electric hammer drill bit body (1). The locking screw (304) is fixedly connected to the electric hammer drill bit body (1) and the hollow drill rod (3) respectively by threads.

6. A lightweight, high-strength electric hammer drill according to claim 5, characterized in that, The upper end of the cutting head (2) is provided with an integrally formed ceramic cutting head (202). The ceramic cutting head (202) is embedded inside the cutting head (2) and is fixedly connected to the cutting head (2) by threads. The surface of the ceramic cutting head (202) is provided with a composite coating, which is a combination of TiAlN multilayer film and DLC coating.

7. A lightweight, high-strength electric hammer drill according to claim 6, characterized in that, A clamping block (306) is installed between the hollow drill rod (3) and the carbon fiber composite rod (305). The clamping block (306) is in contact with the hollow drill rod (3) and the carbon fiber composite rod (305) respectively. A buffer damping pad is provided inside the clamping block (306).

8. A lightweight, high-strength electric hammer drill according to claim 7, characterized in that, The inner side of the carbon fiber composite rod (305) is provided with an integrally formed weight-reducing through-hole (307), and the bottom end of the carbon fiber composite rod (305) is fixedly connected to the through rod (303) by threads.

9. A manufacturing process for a lightweight, high-strength electric hammer drill according to claim 8, characterized in that, Includes the following steps: Step 1: Using precision forging, the blanks of the electric hammer drill bit body (1) and the hollow drill rod (3) are obtained, and the through rod (303) is forged, leaving machining allowance for the locking groove (102); Step 2: Using a CNC lathe and machining center, a locking groove (102) for mechanical interlocking is machined. The roughness of the inner wall of the locking groove (102) is controlled within Ra1.

6. Precision turning is performed at the junction of the electric hammer drill bit body (1) and the hollow drill rod (3) to eliminate step difference, ensure smooth transition of the drill rod outer diameter, and reduce stress concentration. Step 3: Using laser etching, micro-pits and grooves are processed on the mating surface of the hammer drill bit body (1), and the connection port (302) is shaped to enhance the anchoring effect of the connection; Step 4: Eliminate processing stress, refine grains, and prepare for subsequent heat treatment. Heat to 920℃ at a rate of 8-10℃ / s and hold for a period of time. Then cool rapidly in a special quenching medium to obtain a high-hardness martensitic structure. Eliminate quenching stress and stabilize dimensions through stepped tempering. Finally, the main body of the electric hammer drill bit (1) maintains both high hardness and sufficient toughness. Step 5: Sandblast the mating surfaces of the locking groove (102) and the mounting port (301); Step 6: The carbon fiber is woven into a tubular preform. The woven carbon fiber preform is placed into a precision mold using a resin transfer molding process. Low-viscosity high-temperature resin is injected under vacuum negative pressure to ensure that the resin fully impregnates each fiber, thus producing a carbon fiber composite rod (305). Step 6: Place the impregnated mold into an autoclave and cure it by stepwise temperature increase according to the resin curing curve; Step 7: Degrease the mating surface of the installation port (301) with acetone, and grind or plasma treat the connecting end of the carbon fiber tube to remove the release agent and activate the surface to improve the connection strength. Insert the through rod (303), lock the through rod (303) with the internal thread, and drive in the interference fit locking screw (304) to fix the carbon fiber composite rod (305), the hollow drill rod (3) and the electric hammer drill bit body (1). Step 8: Coat the taper barb (203) of the ceramic cutter head (202) with a TiAlN multilayer film and a DLC coating, and sinter it at high temperature to form a brazable fastening mounting groove (201) surface. Assemble the metallized ceramic cutter head (202) taper barb (203) with the locking groove (102) and place it in a vacuum furnace for heating. Step 9: Assemble the connected and combined electric hammer drill bit body (1) into the electric hammer drill (4) to complete the preparation work.

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