Drill bit anti-breaking sleeve for drill pin machining
By designing a drill bit breakage sleeve including a drill clip, a telescopic drill guard and a telescopic control part, the problem of easy breakage in the drill bit during deep hole processing in the prior art is solved, and efficient support and machining accuracy of the drill bit are improved.
Patent Information
- Application Number
- CN202421553022.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-07-03
AI Technical Summary
The existing drill bit breakage sleeve cannot effectively improve the support stiffness of the drill bit, resulting in easy drill bit breakage during deep hole processing.
A drill bit break-proof sleeve including a drill clip, a telescopic drill guard and a telescopic control section are designed. The drill clamping sleeve clamps the drill bit handle, and the telescopic drill guard cover is telescopic to adapt to the deformation of the drill bit. The telescopic control section realizes the automatic retracting of the telescopic drill guard cover through the abutment block and the sleeve ring to ensure that the drill bit is always supported effectively during the processing process.
It effectively improves the support stiffness of the drill bit, prevents excessive bending and breaking of the drill bit, ensures processing accuracy, and discharges processed debris through the chip discharge port.
Smart Images
Figure CN222790700U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of drill bit anti-breakage sleeves, in particular to a drill bit anti-breakage sleeve used for drilling and pinning processing. Background Art
[0002] In the field of mechanical processing, deep hole drilling occupies a very important position. The problem of drill bit breakage is often encountered during deep hole drilling. Especially for deep hole drilling with small hole diameter or deep hole drilling with a large hole depth to hole diameter ratio, drill bit breakage is prone to occur. The main reason for drill bit breakage is that the slender drill bit has poor support stiffness and excessive bending.
[0003] A Chinese patent (authorization announcement number CN 214024567 U, 2021.08.24) discloses an anti-breakage micro drill; it includes a drill body and an anti-breakage protective sleeve, the anti-breakage protective sleeve is axially provided with a coaxially arranged connecting hole and an adjusting hole, the diameter of the connecting hole is smaller than the diameter of the adjusting hole, and an internal thread is provided inside the adjusting hole; the drill body includes a head and a shank, the diameter of the head is the same as the diameter of the shank and the same as the diameter of the connecting hole, the drill body is inserted in the anti-breakage protective sleeve, the end of the head away from the shank extends from the end of the connecting hole away from the adjusting hole, the end of the shank away from the head is located in the adjusting hole, the end of the shank away from the head is connected to an adjusting block, the outer wall of the adjusting block is provided with an external thread adapted to the internal thread, the adjusting block is threadedly connected to the adjusting hole and the adjusting block can move along the axial direction of the adjusting hole. In its technical solution, the length of the drill head extending from the connecting hole is adjustable, which plays a role in supporting and improving the rigidity of the drill bit. However, when it is used for deep hole processing, it still cannot overcome the problem that the drill head extends too long from the connecting hole and its rigidity becomes poor, which makes it easy to break.
[0004] Therefore, how to provide a drill bit anti-breakage sleeve for drilling and pinning, which can effectively improve the support stiffness of the drill bit and thus prevent the drill bit from breaking is a problem that technical personnel in this field urgently need to solve. Utility Model Content
[0005] In view of this, the utility model proposes a drill bit anti-breakage sleeve for drilling and pinning processing, aiming to solve the technical problem that the above-mentioned traditional drill bit anti-breakage sleeve cannot effectively improve the supporting stiffness of the drill bit and the drill bit is prone to breakage during deep hole processing.
[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0007] The utility model provides a drill bit anti-breakage sleeve for drilling and pinning, comprising:
[0008] A drill clamp sleeve, wherein the top end of the drill clamp sleeve has a series of holes opened in the axial direction, and the bottom end of the drill clamp sleeve has a guide hole opened in the axial direction; the series of holes are connected with the guide hole to form a through hole for the drill bit to pass through; the top of the drill clamp sleeve is provided with a drill shank clamping structure for clamping the drill shank;
[0009] A telescopic drill protection sleeve, the top end of which is adapted to be telescopically inserted into the guide hole from the bottom end of the clamping drill sleeve; the telescopic drill protection sleeve has a protective through hole opened in the axial direction for adapting to the penetration of a drill bit;
[0010] The telescopic control part includes a ring mounted on the bottom of the telescopic drill sleeve and an abutment block connected to the bottom end of the ring and corresponding to the circumference of the protective through hole; when the bottom surface of the abutment block abuts against the surface of the workpiece to be drilled, the telescopic drill sleeve can be driven to retract into the guide hole through a reaction force; a chip removal port is formed on the circumference of the abutment block and corresponding to the bottom end of the ring.
[0011] When the utility model is used, a drill bit for processing is inserted into the string hole, the drill bit shank corresponds to the drill shank clamping structure at the top of the drill sleeve, the lower part of the drill bit is correspondingly inserted into the protective through hole, the drill tip of the drill head extends out of the protective through hole and corresponds to the abutment block, and the telescopic drill sleeve can be adjusted to be telescopic in the guide hole so that the bottom end of the abutment block is flush with the tip of the drill bit. The top of the drill sleeve is installed and clamped in the drill chuck of the tool handle, and the tool handle is installed on the main shaft of the machine tool; during drilling and pinning, the tip of the drill bit contacts the workpiece to be drilled while the bottom end face of the abutment block rubs against the surface of the workpiece to be drilled. As the drill bit is fed, the abutment block drives the upper end of the telescopic drill sleeve to gradually retract into the guide hole under the reaction force of friction and pressure; as the drill bit and the drill pin are fed, the protective through hole always adapts to support the body of the drill bit to prevent it from excessive bending and deformation, and plays a role in preventing breakage. The drill sleeve and the telescopic drill sleeve together support the drill bit to improve the support stiffness, thereby ensuring the processing accuracy of the drill bit; processing debris can be discharged from the chip discharge port on the side of the abutment block. The telescopic drill sleeve of the utility model can be telescopic and drill-protected as the drill bit is fed, which can effectively improve the support stiffness of the drill bit and prevent the drill bit from breaking.
[0012] As a further improvement of the above technical solution, the series holes, the guide holes and the protective through holes are all coaxially arranged.
[0013] The beneficial effect of the above technical solution is that the series hole, the guide hole and the protective through hole are coaxially arranged, which improves the stability of the anti-breakage sleeve operation.
[0014] As a further improvement of the above technical solution, a plurality of open grooves penetrating the peripheral wall of the drill clamping sleeve are provided at the top end of the drill clamping sleeve, and the plurality of open grooves are evenly distributed along the circumference of the drill clamping sleeve. The peripheral wall between any two adjacent opening grooves of the drill clamping sleeve forms a clamping claw, and the plurality of clamping claws enclose a drill shank clamping structure that can clamp the shank of a drill bit.
[0015] The beneficial effect of the above technical solution is that the top of the drill sleeve is designed as a drill shank clamping structure composed of a plurality of clamping claws. When the top of the drill sleeve is passed through and installed in a tool handle drill chuck, as the drill chuck is clamped, the plurality of clamping claws of the drill shank clamping structure shrink toward the center, thereby firmly clamping the drill shank.
[0016] As a further improvement of the above technical solution, the outer peripheral wall of the telescopic drill protection sleeve has an external thread, the inner wall of the drill clamping sleeve has an internal thread corresponding to the guide hole, and the telescopic drill protection sleeve and the drill clamping sleeve are adapted to be threadedly connected;
[0017] The collar is fixed on the bottom of the telescopic drill sleeve, and the abutment block is detachably connected to the bottom end of the collar.
[0018] The beneficial effect of the above technical solution is that when the abutment block abuts and rubs against the surface of the workpiece to be drilled, it can rotate under the friction reaction force, the rotating abutment block drives the ring to rotate, the rotating ring drives the telescopic drill guard sleeve to rotate, and the rotating telescopic drill guard sleeve can be gradually screwed into the guide hole of the drill clamping sleeve.
[0019] As a further improvement of the above technical solution, the outer peripheral wall of the telescopic drill protection sleeve and the inner wall of the guide hole are both cylindrical surfaces; the telescopic drill protection sleeve is adapted to be slidably inserted into the guide hole; the collar is rotatably sleeved on the bottom of the telescopic drill protection sleeve; and the abutment block is detachably connected to the bottom end of the collar.
[0020] The beneficial effects of the above technical solution are: the telescopic drill guard sleeve can slide and retract in the guide hole of the drill clamping sleeve, and when the abutment block frictionally abuts against the surface of the workpiece to be drilled, it can rotate under the friction reaction force, and the rotating abutment block drives the collar to rotate; at the same time, as the drill bit feeds the drill pin, the abutment block pushes the collar under the pressure reaction force and then pushes the telescopic drill guard sleeve to gradually slide and retract into the guide hole of the drill clamping sleeve; when the drill bit is used vertically, the telescopic drill guard sleeve can slide under its own weight when the drill bit is retracted to gradually extend out of the guide hole.
[0021] As a further improvement of the above technical solution, there are multiple abutment blocks, and the multiple abutment blocks are evenly distributed along the circumference of the ring.
[0022] The beneficial effect of the above technical solution is that the multiple abutment blocks are evenly distributed along the circumference of the ring to improve the stability of the overall operation.
[0023] As a further improvement of the above technical solution, the abutment block is an elastic rubber block.
[0024] The beneficial effect of the above technical solution is that the abutment block is an elastic rubber block, which can achieve flexible abutment when abutting against the surface of the workpiece to be drilled, thereby avoiding scratches and rigid impacts on the workpiece surface.
[0025] It can be seen from the above technical solution that, compared with the prior art, the utility model discloses a drill bit anti-breakage sleeve for drilling and pinning, which has the following advantages and beneficial effects:
[0026] The utility model realizes effective protection of the drill bit in the whole drilling and pinning process by means of the telescopic drill protection sleeve, effectively improves the supporting rigidity of the drill bit, and further can prevent the drill bit from being excessively bent and broken. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0028] Figure 1 A three-dimensional schematic diagram of the overall structure of a drill bit anti-breakage sleeve used for drilling and pinning processing in the utility model;
[0029] Figure 2 The utility model is a schematic diagram of the interior of a drill bit anti-breakage sleeve used for drilling and pinning;
[0030] Figure 3 The utility model is a structural schematic diagram of a two-stage telescopic drill protection sleeve of a drill bit anti-breakage sleeve used in drilling and pinning processing;
[0031] Figure 4 The utility model discloses a schematic diagram of the internal structure of a two-stage telescopic drill protection sleeve of a drill bit anti-breakage sleeve used in drilling and pinning processing;
[0032] Figure 5 Another structural schematic diagram of a drill bit anti-breakage sleeve for drilling and pinning processing according to the utility model;
[0033] In the figure: 1. drill sleeve; 11. series hole; 12. guide hole; 13. open slot; 14. drill shank clamping structure; 141. clamping claw; 2. telescopic drill sleeve; 21. first-level telescopic drill sleeve; 211. protective through hole; 22. second-level telescopic drill sleeve; 3. telescopic control part; 31. collar; 32. abutment block; 33. chip removal port; 34. bearing; 4. drill bit. DETAILED DESCRIPTION
[0034] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.
[0035] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are 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, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0036] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0037] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0038] like Figures 1 to 4 As shown, a drill bit anti-breakage sleeve for drilling and pinning processing comprises:
[0039] The drill sleeve 1 is cylindrical, and has a top end with a series hole 11 opened in the axial direction, and a bottom end with a guide hole 12 opened in the axial direction; the series hole 11 is connected with the guide hole 12 to form a through hole for the drill bit to pass through; the top of the drill sleeve 1 is provided with a drill shank clamping structure 14 for clamping the drill shank;
[0040] The telescopic drill protection sleeve 2 is cylindrical, and the top of the telescopic drill protection sleeve 2 is adapted to be telescopically inserted into the guide hole 12 by the bottom of the self-clamping drill sleeve 1; the telescopic drill protection sleeve 2 has a protective through hole 211 opened along the axial direction for adapting to the penetration of the drill bit;
[0041] The telescopic control part 3 includes a ring 31 mounted on the bottom of the telescopic drill protection sleeve 2 and an abutment block 32 connected to the bottom end of the ring 31 and corresponding to the surrounding side of the protective through hole 211; when the bottom surface of the abutment block 32 abuts against the surface of the workpiece to be drilled, the telescopic drill protection sleeve 2 can be driven to retract into the guide hole 12 through a reaction force; a chip removal port 33 is formed on the surrounding side of the abutment block 32 and corresponding to the bottom end of the ring 31.
[0042] When this embodiment is used, the drill bit used for processing is inserted into the serial hole 11, the drill bit shank corresponds to the drill shank clamping structure 14 at the top of the drill sleeve 1, and the lower part of the drill bit is correspondingly inserted into the protective through hole 211. The drill tip of the drill head extends out of the protective through hole 211 and corresponds to the abutment block 32. The telescopic drill sleeve 2 can be adjusted to extend and retract in the guide hole 12 so that the bottom end of the abutment block 32 is flush with the tip of the drill bit. The top of the drill sleeve 1 is installed in the drill chuck of the tool handle and is clamped, and the tool handle is installed on the main shaft of the machine tool; during drilling and pinning, the tip of the drill bit contacts the workpiece to be drilled, and the bottom end face of the abutment block 32 rubs against the surface of the workpiece to be drilled. As the drill bit is fed, the abutment block 32 drives the upper end of the telescopic drill sleeve 2 to gradually retract into the guide hole 12 under the friction and pressure reaction force; as the drill bit and the drill pin are fed, the protective through hole 211 is always adapted to support the body of the drill bit to prevent it from excessive bending and deformation, and plays a role in preventing breakage. The drill sleeve 1 and the telescopic drill sleeve 2 jointly support the drill bit to improve the support stiffness, thereby ensuring the processing accuracy of the drill bit; the processing debris can be discharged from the chip discharge port 33 on the side of the abutment block 32. The telescopic drill sleeve 2 of the utility model can be telescopic and drilled as the drill bit is fed, which can effectively improve the support stiffness of the drill bit and prevent the drill bit from breaking.
[0043] In some embodiments, the series holes 11 , the guide holes 12 and the protective through holes 211 are all coaxially arranged.
[0044] The serial hole 11, the guide hole 12 and the protective through hole 211 are coaxially arranged, thereby improving the stability of the anti-break sleeve operation.
[0045] Specifically, the diameter of the series holes 11 is adapted to the outer diameter of the drill bit to be clamped, and the diameter of the series holes 11 is smaller than the diameter of the guide holes 12 ; the diameter of the protective through holes 211 is the same as the diameter of the series holes 11 .
[0046] In some embodiments, a plurality of open grooves 13 penetrating the peripheral wall of the drill sleeve 1 are provided at the top end of the drill sleeve 1 along its radial direction, and the plurality of open grooves 13 are evenly distributed along the circumference of the drill sleeve 1. The peripheral wall between any two adjacent open grooves 13 of the drill sleeve 1 forms a clamping claw 141, and the plurality of clamping claws 141 enclose a drill shank clamping structure 14 that can clamp the shank of a drill bit.
[0047] The top of the drill sleeve 1 is designed as a drill shank clamping structure 14 surrounded by multiple clamping claws 141. When the top of the drill sleeve 1 is installed in the tool handle drill chuck, as the drill chuck is clamped, the multiple clamping claws 141 of the drill shank clamping structure 14 shrink toward the center, which can firmly clamp the drill shank.
[0048] Specifically, the clamping claw 141 can be elastically bent and deformed along the radial direction of the drill sleeve 1 .
[0049] In some embodiments, the outer peripheral wall of the telescopic drill protection sleeve 2 has an external thread, and the inner wall of the drill clamping sleeve 1 has an internal thread corresponding to the guide hole 12, and the telescopic drill protection sleeve 2 and the drill clamping sleeve 1 are adapted to be threadedly connected;
[0050] The collar 31 is sleeved and fixed on the bottom of the telescopic drill protection sleeve 2 , and the abutment block 32 is detachably connected to the bottom end of the collar 31 .
[0051] When the abutment block 32 abuts and rubs against the surface of the workpiece to be drilled, it can rotate under the friction reaction force, the rotating abutment block 32 drives the ring 31 to rotate, and the rotating ring 31 drives the telescopic drill guard sleeve 2 to rotate, and the rotating telescopic drill guard sleeve 2 can be gradually screwed into the guide hole 12 of the drill clamping sleeve 1.
[0052] Specifically, the external thread of the telescopic drill protection sleeve 2 is matched with the internal thread of the drill clamping sleeve 1, and the pitch thereof can be designed according to the needs. When in use, the setting of the single-turn feed amount of the drill bit should be smaller than the size of the pitch.
[0053] In some embodiments, the outer wall of the telescopic drill protection sleeve 2 and the inner wall of the guide hole 12 are both cylindrical surfaces; the telescopic drill protection sleeve 2 is adapted to slide through the guide hole 12; the ring 31 is rotatably sleeved on the bottom of the telescopic drill protection sleeve 2; and the abutment block 32 is detachably connected to the bottom end of the ring 31.
[0054] The telescopic drill protection sleeve 2 can slide and retract in the guide hole 12 of the drill clamping sleeve 1. When the abutment block 32 frictionally abuts against the surface of the workpiece to be drilled, it can rotate under the friction reaction force, and the rotating abutment block 32 drives the ring 31 to rotate; at the same time, as the drill bit feeds the drill pin, the abutment block 32 pushes the ring 31 under the pressure reaction force and then pushes the telescopic drill protection sleeve 2 to gradually slide and retract into the guide hole 12 of the drill clamping sleeve 1; when the drill bit is used vertically, the telescopic drill protection sleeve 2 can slide under its own weight when the drill bit is retracted to gradually extend out of the guide hole 12.
[0055] In some embodiments, there are multiple abutment blocks 32, and the multiple abutment blocks 32 are evenly distributed along the circumference of the ring 31, which can improve the stability of the overall operation.
[0056] Specifically, there are two abutting blocks 32 , and the two abutting blocks 32 are symmetrically arranged on both sides of the protective through hole 211 .
[0057] In some embodiments, the abutment block 32 is an elastic rubber block.
[0058] The abutment block 32 is an elastic rubber block, which can achieve flexible abutment when abutting against the surface of the workpiece to be drilled, thereby avoiding scratches and rigid impacts on the workpiece surface.
[0059] Specifically, the abutment block 32 is detachably connected to the bottom end of the collar 31 by screws or bolts for easy replacement. The abutment block 32 is arranged along the axial direction of the collar 31 in parallel, and the distance from the bottom end surface of the collar 31 to the surface of the workpiece to be drilled can be adjusted by replacing the abutment blocks 32 of different lengths.
[0060] Specifically, the abutment block 32 can also be bonded and fixed to the bottom end of the collar 31, or the abutment block 32 and the collar 31 are designed as an integral structure, and the collar 31 is also made of elastic rubber.
[0061] In some embodiments, the telescopic drill protection sleeve 2 includes a first-level telescopic drill protection sleeve 21 and a second-level telescopic drill protection sleeve 21. The second-level telescopic drill protection sleeve 21 is slidably inserted or threadedly connected in the guide hole 12, and the first-level telescopic drill protection sleeve 21 is slidably inserted or threadedly connected in the center through hole of the second-level telescopic drill protection sleeve 21.
[0062] Specifically, the first-stage telescopic drill protection sleeve 21 , the second-stage telescopic drill protection sleeve 21 and the guide hole 12 have the same length.
[0063] Specifically, the first-level telescopic drill protection sleeve 21 and the second-level telescopic drill protection sleeve 21 are nested and slidably connected, and when the second-level telescopic drill protection sleeve 21 is slidably inserted into the guide hole 12, the collar 31 is rotatably installed at the bottom of the first-level telescopic drill protection sleeve 21 through the bearing 34; the first-level telescopic drill protection sleeve 21 and the second-level telescopic drill protection sleeve 21 are threadedly connected in the center through hole of the second-level telescopic drill protection sleeve 21, and when the second-level telescopic drill protection sleeve 21 is threadedly connected in the guide hole 12, the collar 31 is welded or fixedly installed at the bottom of the first-level telescopic drill protection sleeve 21 by screwing.
[0064] Specifically, the top surface of the collar 31 corresponds to the bottom surface of the secondary telescopic drill protection sleeve 21; as the primary telescopic drill protection sleeve 21 gradually shrinks into the secondary telescopic drill protection sleeve 21, the top surface of the collar 31 can abut against the bottom surface of the secondary telescopic drill protection sleeve 21, and can drive the secondary telescopic drill protection sleeve 21 to shrink into the guide hole 12; of course, the primary telescopic drill protection sleeve 21 can also drive the secondary telescopic drill protection sleeve 21 to gradually shrink into the guide hole 12 through contact friction.
[0065] Specifically, Figure 5 The first-stage telescopic drill protection sleeve 21 and the second-stage telescopic drill protection sleeve 21 shown are both cylindrical structures, and their inner and outer wall surfaces are both cylindrical surfaces, and the inner wall of the guide hole 12 is a cylindrical surface.
[0066] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.
[0067] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.
Claims
1. A drill bit anti-breakage sleeve for drilling and pinning, characterized in that: include: A drill clamp (1), wherein the top end of the drill clamp (1) has a series hole (11) opened in the axial direction, and the bottom end has a guide hole (12) opened in the axial direction; the series hole (11) is connected with the guide hole (12) to form a through hole for a drill bit to pass through; the top of the drill clamp (1) is provided with a drill shank clamping structure (14) for clamping the shank of the drill bit; A telescopic drill protection sleeve (2), the top end of the telescopic drill protection sleeve (2) being adapted to be telescopically inserted into the guide hole (12) from the bottom end of the drill clamp sleeve (1); the telescopic drill protection sleeve (2) having a protective through hole (211) opened in the axial direction for adapting to and inserting a drill bit; A telescopic control part (3), the telescopic control part (3) comprising a collar (31) sleeved on the bottom of the telescopic drill sleeve (2) and a contact block (32) connected to the bottom end of the collar (31) and corresponding to the peripheral side of the protective through hole (211); when the bottom surface of the contact block (32) contacts the surface of the workpiece to be drilled, the telescopic drill sleeve (2) can be driven to retract into the guide hole (12) through a reaction force; a chip removal opening (33) is formed on the peripheral side of the contact block (32) and corresponding to the bottom end of the collar (31).
2. A drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: The series-connected hole (11), the guide hole (12) and the protective through hole (211) are all coaxially arranged.
3. The drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: The top end of the drill clamp sleeve (1) is provided with a plurality of opening grooves (13) penetrating the peripheral wall of the drill clamp sleeve (1); the plurality of opening grooves (13) are evenly distributed along the circumference of the drill clamp sleeve (1); the peripheral wall between any two adjacent opening grooves (13) of the drill clamp sleeve (1) forms a clamping claw (141); the plurality of clamping claws (141) enclose a drill shank clamping structure (14) capable of clamping a drill shank.
4. A drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: The outer peripheral wall of the telescopic drill protection sleeve (2) has an external thread, and the inner wall of the drill clamping sleeve (1) has an internal thread corresponding to the guide hole (12), and the telescopic drill protection sleeve (2) and the drill clamping sleeve (1) are adapted to be threadedly connected; The collar (31) is sleeved and fixed on the bottom of the telescopic drill sleeve (2), and the abutment block (32) is detachably connected to the bottom end of the collar (31).
5. The drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: The outer peripheral wall of the telescopic drill protection sleeve (2) and the inner wall of the guide hole (12) are both cylindrical surfaces; the telescopic drill protection sleeve (2) is adapted to be slidably inserted into the guide hole (12); the collar (31) is rotatably sleeved on the bottom of the telescopic drill protection sleeve (2); and the abutment block (32) is detachably connected to the bottom end of the collar (31).
6. The drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: There are a plurality of abutment blocks (32), and the plurality of abutment blocks (32) are evenly distributed along the circumference of the collar (31).
7. The drill bit anti-breakage sleeve for drilling and pinning according to claim 1, characterized in that: The abutment block (32) is an elastic rubber block.