Drilling device capable of opening holes in normal direction

Abstract

The invention discloses a drilling device for normal drilling, and belongs to the technical field of mechanical drilling tools. The drilling device comprises a drilling device body, a spherical hinge induction slurry disc and a protective shell. An annular inner groove perpendicular to the axial direction is formed in the drilling machine shell, the inner groove penetrates through a rotating shaft of the drilling machine, and a plurality of ball holes are evenly distributed in the periphery of the rotating shaft and used for being hinged to a plurality of ball hinge induction slurry discs in a one-to-one correspondence mode. When the drilling device works, the spherical hinge induction slurry disc rotates along with the rotating shaft, and the protective shell seals the notch of the inner groove. The spherical hinge induction paddle disc is in equal clearance fit with the two axial sides of the inner groove, the end face, close to the drill bit installation end, of the inner groove is metalized, and the end face and the spherical hinge induction paddle disc made of the conductive material form a normally-open contact switch which is connected into a control circuit of the drill. And when the inclination of the drilling device exceeds the range, the normally open contact switch is closed, and the drilling device gives an alarm. Automatic control over normal drilling of the drilling device is achieved, an external auxiliary tool is avoided, and the requirement for the perpendicularity of drilling is met.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical drilling tools, and in particular relates to a drill for normal hole drilling. Background Art

[0002] Drilling is one of the most common machining methods and is widely used in the connection and assembly of various parts, components and assemblies. Handheld electric drills are commonly used drills. During drilling operations, due to the eccentric force applied by the operator to the drill, the drilled hole may not be perpendicular to the machining plane of the object, resulting in a reduction in the connection strength between the drilled hole and the connecting part or failure, and even leading to the scrapping of parts, components and assemblies, resulting in losses in manpower, material and financial resources.

[0003] In order to solve the above problems and realize normal vertical drilling with a manual handheld drill, it is generally necessary to design auxiliary tooling to be used with the drill, and to limit the drill bit deflection of the drill through the auxiliary tooling. However, this solution has the following defects: 1. The auxiliary tooling and the drill need to be installed during use, which is time-consuming and labor-intensive; 2. The auxiliary tooling and the drill are generally independent devices, and the auxiliary tooling may leak; 3. In some specific drilling scenarios, the auxiliary tooling may interfere with the parts to be processed, making it impossible to use, or blocking the hole position and making it difficult to perform drilling operations. Summary of the invention

[0004] Technical issues to be solved:

[0005] In order to avoid the shortcomings of the prior art, the present invention provides a drill for normal hole drilling, which improves the handheld drill. A ball-hinged sensing paddle disc is arranged on the drill body, and a normally open contact switch is formed between the ball-hinged sensing paddle disc and the casing of the drill. The normally open contact switch is connected to the control circuit of the drill as a control switch, so that an alarm is issued when the drill exceeds the tilt range, thereby realizing automatic control of the normal drilling of the drill and avoiding the use of external auxiliary tooling to ensure the verticality requirement of the drilling.

[0006] The technical solution of the present invention is: a normal hole drilling tool, comprising a drilling tool body, a ball-jointed induction slurry disc and a protective shell;

[0007] The casing of the drill near the drill bit mounting end is provided with an annular inner groove perpendicular to the axial direction of the casing, which is used to embed and install the ball-jointed induction slurry disc; the inner groove radially penetrates the rotating shaft of the core of the drill, and the outer diameter wall of the circumference of the rotating shaft is located at the axial center of the inner groove and is evenly distributed with a plurality of ball holes, which are used to be hinged with a plurality of ball-jointed induction slurry discs in a one-to-one correspondence; when the drill is working, the ball-jointed induction slurry disc rotates with the rotating shaft; the protective shell is used to close the notch of the inner groove;

[0008] The ball-jointed induction paddle disc comprises a ball-jointed head, a connecting rod and a paddle disc, wherein the ball-jointed head is coaxially fixedly connected to the paddle disc through the connecting rod, the ball-jointed head is hinged to the spherical surface of the ball hole of the rotating shaft, and the paddle disc is matched with equal clearances on both sides of the axial direction of the inner groove; the end face of the inner groove close to the drill bit mounting end is metallized, and forms a normally open contact switch with the ball-jointed induction paddle disc of conductive material when the drill is working, and is electrically connected to the control circuit of the drill, and when the normally open contact switch is closed, the drill sends out an alarm.

[0009] A further technical solution of the present invention is that the ball joint head is spherical, and a cross-shaped contraction groove is provided along one end of the ball joint head facing away from the connecting rod for realizing elastic contraction installation of the ball joint head, and the ball joint head is embedded in the ball hole of the rotating shaft and spherically hinged with it.

[0010] A further technical solution of the present invention is: the paddle disk is provided with a first side surface and a second side surface which are parallel to each other, the distance between the first side surface and the second side surface is L1, L1 is smaller than the axial width L2 of the inner groove, and the first side surface faces the metallized end surface of the inner groove.

[0011] A further technical solution of the present invention is: the condition for the normally open contact switch to be closed is: when the drilling device is working and the tilt range exceeds A, the first side surface of the slurry disc contacts the metallized end surface of the inner groove;

[0012] A is the maximum angle at which the drill can be tilted:

[0013]

[0014] Where R is the distance from the center of the ball joint to the end of the propeller disc away from the ball joint.

[0015] A further technical solution of the present invention is: the control circuit of the drill includes two branches connected in parallel, one of which is connected in series with a normally open contact switch, an electromagnetic coil of an AC contactor and a buzzer in sequence; the other branch is connected in series with a first button, a normally closed contact of the AC contactor and a motor of the drill in sequence, wherein the normally closed contact of the AC contactor is connected in parallel with a branch circuit composed of a second button and a normally open contact of the AC contactor in series.

[0016] A further technical solution of the present invention is: the ball-jointed induction paddle disc is connected to the control circuit through a cable and a carbon brush, and the carbon brush includes an outer ring, an inner ring and a power ball; the inner ring is coaxially mounted and fixed to the outer diameter of the rotating shaft of the drill; the outer ring is fixedly installed in the drill casing and coaxially matched with the inner ring, and a slide groove for the power ball is formed between the outer diameter of the inner ring and the inner diameter of the outer ring; the power ball is slidably installed in the slide groove, one end of the cable is electrically connected to the ball-jointed induction paddle disc, and the other end is electrically connected to the power ball, and the outer ring of the carbon brush is electrically connected to the control circuit.

[0017] A further technical solution of the present invention is: the rotating shaft has at least three ball holes, corresponding to which three ball-jointed induction paddle discs are installed.

[0018] A further technical solution of the present invention is that the ball joint induction paddle disc is an integral structure, and the paddle disc is a rectangular parallelepiped structure, and one end of the paddle disc facing away from the ball joint head is in clearance fit with the inner wall of the protective shell.

[0019] A further technical solution of the present invention is: the protective shell is a two-half-ring docking structure, and its axial width is greater than the axial width of the inner groove; the notch of the inner groove is symmetrically provided with sunken steps on both sides for embedding the protective shell and bonding and fixing it to the protective shell.

[0020] A further technical solution of the present invention is that the casing and the protective casing are both made of insulating materials.

[0021] Beneficial Effects

[0022] The beneficial effects of the present invention are as follows: the present invention is a normal hole drilling drill, by modifying a handheld drill, setting an inner groove in the drill housing, installing a ball-jointed inductive paddle disc in the inner groove, and the ball-jointed inductive paddle disc is hinged with the rotating shaft of the drill, and rotates with it when working. The ball-jointed inductive paddle disc with conductive function and the metallized end face of the inner groove of the housing form a normally open contact switch SB2, which is connected to the control circuit of the drill. When the drill works normally, SB2 is normally open; when the inclination angle of the drill exceeds A, the paddle disc of the ball-jointed inductive paddle disc contacts the metallized end face of the inner groove of the housing, so that SB2 is closed, the drill alarm is controlled or the drill motor stops, and the automatic control of the normal drilling of the drill is realized.

[0023] The present invention forms a contact switch through the ball joint induction paddle disc and the metallized end of the inner groove, and cooperates with the control circuit of the drill to enable the drill to achieve the verticality requirement of drilling within the allowable tilt range. The design of conventional external drilling auxiliary tooling is omitted, and the control of normal drilling is achieved by the drill itself, which eliminates the need for installation and carrying of auxiliary tooling, and also avoids the obstruction of the drilling hole position by the external auxiliary drilling tooling and possible interference problems, thereby achieving the simplification of the drilling tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the three-dimensional solid structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the internal structure of the ball joint induction slurry disc installation location of the present invention;

[0026] Figure 3 A schematic diagram of the maximum angle A at which the drill is allowed to tilt according to the present invention;

[0027] Figure 4 It is a schematic diagram of the metallized end surface of the inner groove of the present invention;

[0028] Figure 5 It is the control circuit principle diagram of the present invention;

[0029] Figure 6 It is a schematic diagram of the structure of the ball-jointed induction paddle disc of the present invention;

[0030] Figure 7 It is a schematic diagram of the carbon brush structure of the present invention.

[0031] Explanation of the reference numerals: 1. Drill, 11. Drill bit, 12. Casing, 13. Inner groove, 131. Metallized end face, 14. Rotating shaft, 2. Ball joint induction paddle disc, 21. Ball joint head, 211. Contraction groove, 22. Connecting rod, 23. Paddle disc, 231. First side, 232. Second side, 3. Protective shell, SB2. Normally open contact switch, KM1. Electromagnetic coil of AC contactor, 4. Buzzer, 5. First button, KM1'. Normally closed contact of AC contactor, 6. Motor, 7. Second button, KM1". Normally open contact of AC contactor, 8. Carbon brush, 81. Outer ring, 82. Inner ring, 83. Power ball, 84. Slide groove, 9. Cable. DETAILED DESCRIPTION

[0032] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0033] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0034] The present embodiment provides a drill for normal hole drilling, including a drill body 1. The drill body 1 is improved by adding a ball-hinged inductive paddle disc 2 and a protective shell 3 to the drill body 1, so that the ball-hinged inductive paddle disc 2 and the housing 12 of the drill 1 form a normally open contact switch, which is connected to the control circuit of the drill 1 as a control switch. By designing a matching control circuit, automatic control of normal drilling of the drill 1 is achieved to solve the problem that the drill 1 is prone to deflection during drilling operation, and the use of external auxiliary tooling has problems such as cumbersome loading and unloading, interference or obstruction of the operation.

[0035] like Figure 1 , 2As shown, the rear end of the drill 1 is a handheld part, and the front end is equipped with a drill bit 11. When drilling, the drill bit 11 is perpendicular to the surface of the object to be drilled, and the drill bit 11 is driven by the rotating shaft 14 in the drill 1 and rotates coaxially with the rotating shaft 14. An annular inner groove 13 is provided on the housing 12 of the drill 1 near the installation end of the drill bit 11, perpendicular to the axial direction of the housing 12 (that is, the installation axial direction of the drill bit 11), for embedding and installing the ball-jointed induction slurry disc 2. The inner groove 13 passes through the rotating shaft 14 at the core of the drill 1, and the outer diameter wall of the circumference of the rotating shaft 14 is located at the axial center of the inner groove 13. There are 4 ball holes evenly distributed, which are used to be hinged with the 4 ball-jointed induction slurry discs 2 one by one. The cross-section of the inner groove 13 is rectangular, and the width along the axial direction is L2. The end face of the inner groove 13 near the installation end of the drill bit 11 is metallized. The housing 12 is made of insulating material.

[0036] like Figure 2 , 3 As shown in Figures 4 and 6, the ball-jointed inductive paddle disc 2 includes a ball-jointed head 21, a connecting rod 22 and a paddle disc 23. The ball-jointed head 21 is coaxially fixedly connected with the paddle disc 23 through the connecting rod 22. The ball-jointed head 21 is spherical. A cross-shaped contraction groove 211 is arranged along one end of the ball-jointed head 21 facing away from the connecting rod 22, so as to facilitate the elastic contraction of the ball-jointed head 21 and facilitate installation. The ball-jointed head 21 is embedded in the ball hole of the rotating shaft 14 and is spherically hinged therewith. The connecting rod 22 is rod-shaped, one end of which is connected to the ball-jointed head 21, and the other end is connected to the paddle disc 23. The paddle disc 23 is a rectangular parallelepiped structure, and is matched with equal clearances on both axial sides of the inner groove 13. The distance between the first side surface 231 and the second side surface 232 of the paddle disc 23 is L1, and L1 is smaller than the axial width L2 of the inner groove 13. The first side surface 231 faces the metallized end surface 131 of the inner groove 13, and the second side surface 232 faces the other axial inner end surface of the inner groove 13. When the drill 1 is working, the ball-jointed inductive paddle disc 2 rotates along with the rotating shaft 14. In this embodiment, the ball-jointed inductive paddle disc 2 is an integral structure, and the material is a conductive material.

[0037] like Figure 2 As shown, the protective shell 3 is annular and is used to close the notch of the inner groove 13, and to enclose the ball joint induction paddle disc 2 in the inner groove 13. The protective shell 3 is a two-half ring docking structure, made of insulating material, and its axial width is greater than the axial width of the inner groove 13. In order to cooperate with the installation of the protective shell 3, sunken steps are symmetrically provided on both sides of the notch of the inner groove 13, and the protective shell 3 is embedded in the sunken steps and bonded and fixed thereto. The outer diameter of the protective shell 3 is the same as the outer diameter of the casing 12, so that the connection between the casing 12 and the protective shell 3 is smooth and flat; the inner wall of the protective shell 3 is clearance-matched with the outer end of the paddle disc 23 away from the ball joint head 21 to avoid interference between the ball joint induction paddle disc 2 and the protective shell 3 during rotation.

[0038] The ball-jointed inductive paddle disc 2 is electrically connected to the control circuit of the drill 1, and the metallized end surface 131 of the inner groove 13 is electrically connected to the control circuit of the drill 1. The ball-jointed inductive paddle disc 2 and the metallized end surface 131 of the inner groove 13 form a normally open contact switch SB2 in the control circuit. When the drill 1 exceeds the restricted tilt angle range during operation, the normally open contact switch SB2 is closed, and the drill 1 issues an alarm or the motor 6 stops rotating.

[0039] like Figure 3 As shown, when the drill bit of the drill 1 is perpendicular to the object and drills normally, there is a gap between the ball joint induction paddle disc 2 and the metallized end surface 131 of the inner groove 13, and the normally open contact switch SB2 is in the open state. The condition for the normally open contact switch SB2 to be closed is: when the drill 1 is working, the tilt range exceeds A, and the first side surface 231 of the paddle disc 23 contacts the metallized end surface 131 of the inner groove. A is the maximum angle allowed for the drill 1 to tilt, which is determined according to the axial width L2 of the inner groove 13 and the axial thickness L1 of the paddle disc 23. The specific calculation formula is:

[0040]

[0041] In the formula, L1 is the distance between the first side 231 and the second side 232 of the paddle disc 23, that is, the axial thickness of the paddle disc 23; L2 is the axial width of the inner groove 13; R is the distance from the center of the ball joint 21 to the end of the paddle disc 23 away from the ball joint 21.

[0042] like Figure 5 As shown, the control circuit of the drill 1 includes two branches connected in parallel, one of which is connected in series with the normally open contact switch SB2, the electromagnetic coil KM1 of the AC contactor and the buzzer 4. The other branch is connected in series with the first button 5, the normally closed contact KM1' of the AC contactor and the motor 6 of the drill, wherein the normally closed contact KM1' of the AC contactor is connected in parallel with the branch circuit connected in series with the second button 7 and the normally open contact KM1" of the AC contactor. Both ends of the control circuit are connected to the power supply of the drill 1.

[0043] like Figure 2 , 7As shown, the ball-jointed induction slurry disc 2 is connected to the control circuit through a cable and a carbon brush 8. The carbon brush 8 includes an outer ring 81, an inner ring 82 and a power ball 83. The carbon brush 8 is made of conductive material. The inner ring 82 is coaxially fixed to the outer diameter of the drilling shaft 14. The outer ring 81 is fixedly installed in the drilling housing 12. The inner ring 82 is coaxial with the outer ring 81 and used in conjunction with each other. A slide groove 84 for the power ball 83 is formed between the outer diameter of the inner ring 82 and the inner diameter of the outer ring 81. The cross section of the slide groove 84 matches the power ball 83. The power ball 83 is spherical and is slidably installed in the slide groove 84. Its spherical surface contacts the inner ring 82 and the outer ring 81 at the same time. A wiring hole for the cable to pass through is provided in the rotating shaft 14. The cable 9 is installed in the wiring hole. One end of the cable is electrically connected to the ball-jointed induction slurry disc 2, and the other end is electrically connected to the power ball 83. An annular groove is provided in the axial middle position of the inner ring 82, which is connected with the slide groove 84 for passing the cable 9. When the rotating shaft 14 rotates, the power ball 83 slides in the slide groove 84 and rotates synchronously with the ball joint induction paddle disc 2. The outer ring 81 of the carbon brush is electrically connected to the control circuit, thereby connecting the ball joint induction paddle disc 2 to the control circuit. The metallized end surface 131 of the inner groove is connected to the control circuit through a cable.

[0044] See also Figure 2 , 5 The specific working principle of the drill 1 of the present invention is as follows:

[0045] When the drill 1 is in a horizontal working state, that is, the drill bit 11 at the front end of the drill 1 is horizontal, and a hole needs to be drilled on a working surface perpendicular to the horizontal plane: when the drill 1 is ready to be started, the second button 7 is in a disconnected state, the ball-jointed inductive paddle disc 2 is perpendicular to the horizontal plane under its own gravity, and a gap of (L2-L1) / 2 is formed between the ball-jointed inductive paddle disc 2 and the metallized end surface 131 of the inner groove, and the normally open contact switch SB2 is in a disconnected state. Press the first button 5 for controlling the rotation of the motor 6, the motor 6 rotates, and normal drilling is started. When the drill 1 tilts during the drilling process, causing the drill bit 11 and the rotating shaft 14 to tilt, and the tilt angle exceeds the allowable angle A, the ball-jointed inductive paddle disc 2, under the influence of gravity and the universal ball joint with the rotating shaft 14, the paddle disc 23 contacts the metallized end surface 131 of the inner groove, realizing the closure of SB2. At this time, the buzzer 4 sounds an alarm to indicate that the tilt angle exceeds the limit. At the same time, the electromagnetic coil KM1 of the AC contactor is energized to disconnect the normally closed contact KM1' of the AC contactor, the motor 6 stops, and the drill 1 stops drilling.

[0046] When the drill 1 is in a vertical working state, that is, the drill bit 11 at the front end of the drill 1 is perpendicular to the horizontal plane, and it is necessary to drill a hole on the horizontal working surface: first press the second button 7 to start the non-horizontal drilling mode, and then press the first button 5. Under the action of gravity, the ball-jointed inductive paddle disc 2 contacts the metallized end surface 131 of the inner groove, that is, in the initial state, the normally open contact switch SB2 is closed, the electromagnetic coil KM1 of the AC contactor is energized, the normally open contact KM1" of the AC contactor is closed, and the motor 6 starts to rotate. At this time, the buzzer 4 will emit a short noise). Under the action of centrifugal force, the ball-jointed inductive paddle disc 2 gradually balances with gravity, so that the ball-jointed inductive paddle disc 2 is separated from the metallized end surface 131 of the inner groove, and the normally open contact switch SB2 is disconnected, the buzzer 4 stops making noise, and at the same time, the electromagnetic coil KM1 of the AC contactor is de-energized, so that the normally closed contact KM1' of the AC contactor is closed, the normally open contact KM1" of the AC contactor is opened, and the motor 6 works normally for drilling. When the drill 1 tilts during the drilling process, the drill bit 11 and the shaft 14 tilt, and the tilt angle exceeds the allowable angle A, the ball-jointed inductive paddle disc 2 cannot tilt along with the shaft 14 at the same time under the influence of the rotational inertia force and the universal ball joint with the shaft 14, so that the paddle disc 23 contacts the metallized end surface 131 of the inner groove, SB2 is closed, and the buzzer 4 sounds an alarm. At this time, the electromagnetic coil KM1 of the AC contactor is energized, so that the normally closed contact KM1' of the AC contactor is opened, and the normally open contact KM1" of the AC contactor is closed, and the motor 6 continues to rotate. The buzzer 4 alarms to indicate that the tilt angle exceeds the limit, reminding the operator to stop drilling and adjust the angle, or to turn off the first button 5 to manually stop the rotation of the motor 6.

[0047] It should be noted that the drill 1 of the present invention is not limited to the above two working states, and can be operated on a working surface at any angle. The vertical working state of the drill 1 is a gravity limit working state of the ball joint induction paddle disc 2. The second button 7 is used as a state selection switch of the drill 1, and is used in the vertical working state or the inclined working state of the drill 1. The first button 5 is used as the main control switch of the motor 6, and has a spring reset function.

[0048] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and intent of the present invention.

Claims

1. A normal hole drilling tool, comprising a drilling tool body, characterized in that: Also includes a ball-jointed induction paddle disc and a protective shell; The casing of the drill near the drill bit mounting end is provided with an annular inner groove perpendicular to the axial direction of the casing, which is used to embed and install the ball-jointed induction slurry disc; the inner groove radially penetrates the rotating shaft of the core of the drill, and the outer diameter wall of the circumference of the rotating shaft is located at the axial center of the inner groove and is evenly distributed with a plurality of ball holes, which are used to be hinged with a plurality of ball-jointed induction slurry discs in a one-to-one correspondence; when the drill is working, the ball-jointed induction slurry disc rotates with the rotating shaft; the protective shell is used to close the notch of the inner groove; The ball-jointed induction paddle disc comprises a ball-jointed head, a connecting rod and a paddle disc, wherein the ball-jointed head is coaxially fixedly connected to the paddle disc through the connecting rod, the ball-jointed head is hinged to the spherical surface of the ball hole of the rotating shaft, and the paddle disc is matched with equal clearances on both sides of the axial direction of the inner groove; the end face of the inner groove close to the drill bit mounting end is metallized, and forms a normally open contact switch with the ball-jointed induction paddle disc made of conductive material when the drill is working, and is electrically connected to the control circuit of the drill, and when the normally open contact switch is closed, the drill sends out an alarm.

2. The normal hole drilling tool according to claim 1, characterized in that: The ball joint head is spherical, and a cross-shaped contraction groove is arranged along one end of the ball joint head facing away from the connecting rod, which is used to realize the elastic contraction installation of the ball joint head. The ball joint head is embedded in the ball hole of the rotating shaft and is spherically hinged with it.

3. The normal hole drilling tool according to claim 1, characterized in that: The paddle disk is provided with a first side surface and a second side surface which are parallel to each other. The distance between the first side surface and the second side surface is L1, and L1 is smaller than the axial width L2 of the inner groove. The first side surface faces the metallized end surface of the inner groove.

4. The normal hole drilling tool according to claim 3, characterized in that: The condition for the normally open contact switch to be closed is: when the drilling device 1 is working, the tilt range exceeds A, and the first side surface of the slurry disc contacts the metallized end surface of the inner groove; A is the maximum angle at which the drill can be tilted: Where R is the distance from the center of the ball joint to the end of the propeller disc away from the ball joint.

5. The normal hole drilling tool according to claim 1, characterized in that: The control circuit of the drill includes two branches connected in parallel, one of which is connected in series with a normally open contact switch, an electromagnetic coil of an AC contactor, and a buzzer in sequence; the other branch is connected in series with a first button, a normally closed contact of the AC contactor, and a motor of the drill in sequence, wherein the normally closed contact of the AC contactor is connected in parallel with a branch circuit in which a second button and a normally open contact of the AC contactor are connected in series.

6. The normal hole drilling tool according to claim 5, characterized in that: The ball-jointed induction paddle disc is connected to the control circuit via a cable and a carbon brush, and the carbon brush comprises an outer ring, an inner ring and a power receiving ball; the inner ring is coaxially mounted and fixed to the outer diameter of the rotating shaft of the drill; the outer ring is fixedly installed in the drill housing and coaxially cooperates with the inner ring, and a slide groove for the power receiving ball is formed between the outer diameter of the inner ring and the inner diameter of the outer ring; the power receiving ball is slidably installed in the slide groove, one end of the cable is electrically connected to the ball-jointed induction paddle disc, and the other end is electrically connected to the power receiving ball, and the outer ring of the carbon brush is electrically connected to the control circuit.

7. The normal hole drilling tool according to claim 1, characterized in that: The rotating shaft has at least three ball holes, corresponding to which three ball-jointed induction paddle discs are installed.

8. The normal hole drilling tool according to claim 1, characterized in that: The ball joint induction paddle disc is an integral structure, and its paddle disc is a rectangular parallelepiped structure, and one end of the paddle disc facing away from the ball joint head is in clearance fit with the inner wall of the protective shell.

9. The normal hole drilling tool according to claim 1, characterized in that: The protective shell is a two-half-ring docking structure, and its axial width is greater than the axial width of the inner groove; the notch of the inner groove is symmetrically provided with sunken steps on both sides for embedding the protective shell and bonding and fixing with the protective shell 3.

10. The normal hole drilling tool according to claim 1, characterized in that: The casing and the protective casing are both made of insulating materials.

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