Quick-change device for replacing punching hollow drill

Abstract

The utility model discloses a quick-change device for replacing a punching hollow drill, which comprises a quick-change chuck body, the upper part of the quick-change chuck body is arranged on a power shaft, the lower part of the quick-change chuck body is provided with an insertion hole for inserting the hollow drill, the lower end of the quick-change chuck body extends outwards to form a chuck platform, and the side wall of the quick-change chuck body is provided with an accommodating through hole for accommodating a ball. The outer side of the quick-change chuck body is sleeved with a quick-change chuck sleeve, the inner side face of the lower portion of the quick-change chuck sleeve is an inclined face making contact with the balls, and a containing space for containing a reset spring is formed between the inner side face of the upper portion of the quick-change chuck sleeve and the outer side face of the quick-change chuck body. A quick-change chuck nut for compressing the reset spring is arranged on the outer side of the quick-change chuck body above the reset spring, and the reset spring is compressed and used for applying pressure to the quick-change chuck sleeve, so that the inclined plane moves downwards and is separated from the ball, and the upper end of the inclined plane extrudes the ball into the clamping hole. The hollow drill can be rapidly replaced without tools, and the efficiency of replacing the hollow drill is high.

Description

Technical Field

[0001] The utility model belongs to the technical field of cutting machines, and in particular relates to a quick-changing device for replacing a punching hollow drill. Background Art

[0002] Hollow drill is also known as core drill, steel plate drill and hole drill. Its standard name is multi-blade steel plate drill. It adopts multi-blade annular cutting. The drill bit only cuts the outer diameter annular part of the hole, and does not cut the middle part, thereby greatly improving the drilling efficiency. Combined with magnetic base drilling rigs, it can realize drilling operations on site at any time. Compared with ordinary twist drills, it is more efficient and cuts faster.

[0003] Currently in the cutting machine industry, operators mostly need tools to assist in replacing the hollow drill used for drilling, and there are many operating steps. Therefore, the efficiency of replacing the hollow drill used for drilling is not high, which slows down the drilling speed. Utility Model Content

[0004] In view of the above-mentioned defects of the prior art, the utility model provides a quick-change device for replacing a hollow drill for drilling, which can quickly replace the hollow drill without the aid of tools, and the efficiency of replacing the hollow drill is high.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A quick-change device for replacing a perforating hollow drill comprises a quick-change chuck body, the upper part of which is detachably connected to a power shaft of a motor and the lower part of which is provided with a socket for inserting a hollow drill tail, the lower end of which extends outward to form a chuck platform, the side wall of which is provided with a through hole for accommodating a ball, the through hole corresponding to the clamping hole of the hollow drill tail, a quick-change chuck sleeve sleeved on the outer side of the quick-change chuck body, the lower part of which is provided with a socket for inserting a hollow drill tail, the lower end ... the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting a hollow drill tail, the lower end of the socket for inserting The inner surface is an inclined surface that is inclined downward and outward and contacts the ball, and an accommodating space for accommodating a reset spring is formed between the inner surface of the upper part of the quick-change chuck sleeve and the outer surface of the quick-change chuck body. A quick-change chuck nut that compresses the reset spring is provided on the outer side of the quick-change chuck body above the reset spring. The reset spring is compressed and used to apply pressure to the quick-change chuck sleeve, so that the inclined surface moves downward and separates from the ball, and the upper end of the inclined surface squeezes the ball into the clamping hole, and the lower end of the quick-change chuck sleeve abuts against the chuck platform.

[0007] Furthermore, the quick-change chuck body is cylindrical in shape, and a buffer gasket is provided on the top surface of the chuck platform.

[0008] Furthermore, the upper portion of the quick-change chuck body is sleeved on the outer side of the power shaft and is threadedly connected to the power shaft.

[0009] Furthermore, a plurality of anti-loosening screws abutting against the side surface of the power shaft are inserted on the upper side wall of the quick-change chuck body.

[0010] Furthermore, the lower inner side surface and the upper inner side surface of the quick-change chuck sleeve are connected via a horizontal clamping surface, the lower end of the reset spring abuts against the clamping surface and the upper end abuts against the lower end surface of the quick-change chuck nut.

[0011] Furthermore, the inner side surface of the quick-change chuck sleeve below the clamping surface includes a lower pressure surface, an inclined surface and an upper pressure surface from bottom to top, and the lower pressure surface, the upper pressure surface and the inner side surface of the quick-change chuck sleeve above the clamping surface are all vertical cylindrical surfaces, and the inclined surface is a conical surface with the cone tip facing downward.

[0012] Furthermore, the inner side surface of the quick-change chuck sleeve on the upper side of the pressing surface is located on the outer side of the quick-change chuck nut.

[0013] Furthermore, there are multiple accommodating through holes and they are all in the shape of a cone, the small diameter end of each accommodating through hole is on the inner side surface of the quick-change chuck body, and there are multiple clamping holes and they are all in the shape of a cone, the cone tip of each clamping hole faces the inner side surface of the tail of the hollow drill, and each of the accommodating through holes corresponds to the position of the corresponding clamping hole.

[0014] Furthermore, the plurality of accommodating through holes are evenly distributed on the side wall of the quick-change chuck body at the insertion hole.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] The utility model provides a quick-change device for replacing a punching hollow drill, before the tail of the hollow drill is not inserted into the insertion hole of the quick-change chuck body, the quick-change chuck nut is not screwed on the outside of the quick-change chuck body, the reset spring is in a naturally extended state, the inclined surface of the quick-change chuck sleeve contacts the ball, the ball is on the outside of the accommodating through hole, when the hollow drill needs to be locked, the tail of the hollow drill is inserted into the insertion hole of the quick-change chuck body, wherein the accommodating through hole corresponds to the clamping hole of the tail of the hollow drill, and the quick-change chuck nut is screwed on the outside of the quick-change chuck body and the number of rotations of the quick-change chuck nut is adjusted to provide corresponding pressure on the reset spring, the reset spring is compressed and applies downward pressure to the quick-change chuck sleeve, so that the inclined surface of the quick-change chuck sleeve moves downward The hollow drill is moved and separated from the ball, and the upper end of the inclined surface squeezes the ball to the inner side of the accommodating through hole and the clamping hole, and the lower end of the quick-change chuck sleeve abuts against the chuck platform, so that the hollow drill and the quick-change chuck body are locked, and the hollow drill is driven by the power shaft to perform a drilling action; when it is necessary to unlock the hollow drill, the operator pulls up the quick-change chuck sleeve and moves the inclined surface up, the upper end of the inclined surface is separated from the ball, and the ball withdraws from the clamping hole and retreats to the outside of the accommodating through hole due to the loss of squeezing force, so that the ball is separated from the clamping hole, and the operator pulls out the hollow drill downward to unlock the hollow drill and the quick-change chuck body; therefore, the hollow drill can be replaced conveniently and quickly without the aid of tools, and the efficiency of replacing the hollow drill is high, thereby speeding up the drilling speed.

[0017] In the utility model, a buffer gasket is provided on the top surface of the chuck platform; when the hollow drill is unlocked, the quick-change chuck sleeve is pulled up to further compress the reset spring, and the quick-change chuck sleeve is released after the hollow drill is pulled out, and the reset spring stretches and resets and generates a downward force on the quick-change chuck sleeve. The quick-change chuck sleeve moves downward under the downward force of the reset spring and its own gravity and hits the buffer gasket of the chuck platform. The setting of the buffer gasket can play a buffering role on the quick-change chuck sleeve, reduce the impact force generated by the quick-change chuck sleeve on the quick-change chuck body when the reset spring is reset, improve the service life of the quick-change chuck sleeve and the quick-change chuck body, and reduce noise.

[0018] In the utility model, for reset springs of different specifications, by adjusting the number of rotations of the quick-change chuck nut, a stable pressure can be applied to the reset spring, and then the reset spring is compressed and a stable downward pressure is applied to the quick-change chuck sleeve, so that the inclined surface of the quick-change chuck sleeve moves downward and separates from the ball, and the upper end of the inclined surface squeezes the ball into the clamping hole, and the lower end of the quick-change chuck sleeve abuts against the chuck platform, so that a stable locking force can be provided to the hollow drill, and a stable torque can be provided to the hollow drill; in addition, for reset springs of the same specification, by adjusting the number of rotations of the quick-change chuck nut, different pressures can be applied to the reset spring, and then the reset spring is compressed and a different downward pressure is applied to the quick-change chuck sleeve, so that the extrusion force applied to the ball in the process of the upper end of the inclined surface squeezing the ball into the clamping hole is different, so different locking forces can be provided to the hollow drill, and different torques can be provided to the hollow drill, and in addition, according to the required maximum torque of the hollow drill, the required maximum torque of the hollow drill can be set by adjusting the number of rotations of the quick-change chuck nut to improve the life of the hollow drill. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a cross-sectional structural schematic diagram of a quick-change device for replacing a perforating hollow drill when the hollow drill of the utility model is in a locked state;

[0020] Figure 2 It is a schematic cross-sectional structural diagram of a quick-change device for replacing a punching hollow drill when the hollow drill is in an unlocked state by pulling up a quick-change chuck sleeve in the utility model.

[0021] Explanation of the reference numerals in the figure: 1. quick-change chuck sleeve, 101. inclined surface, 102. clamping surface, 103. lower pressure surface, 104. upper pressure surface, 2. quick-change chuck nut, 3. quick-change chuck body, 301. chuck platform, 302. accommodating through hole, 4. buffer gasket, 5. return spring, 6. ball bearing, 7. anti-loosening screw, 8. hollow drill, 801. clamping hole, 9. power shaft, 10. accommodating space. DETAILED DESCRIPTION

[0022] The following is a further detailed description of the specific implementations of the present invention in conjunction with the accompanying drawings. These implementations are only used to illustrate the present invention, but not to limit the present invention.

[0023] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions 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. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In addition, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0026] like Figure 1 and Figure 2 As shown, a quick-change device for replacing a perforating hollow drill comprises a quick-change chuck body 3, the upper portion of the quick-change chuck body 3 is detachably connected to the power shaft 9 of the motor and the lower portion is provided with a socket for inserting the tail of the hollow drill 8, the lower end of the quick-change chuck body 3 extends outward to form a chuck platform 301, and the side wall of the quick-change chuck body 3 at the socket is provided with a receiving through hole 302 for accommodating a ball 6, and the receiving through hole 302 corresponds to the clamping hole 801 at the tail of the hollow drill 8, a quick-change chuck sleeve 1 is sleeved on the outer side of the quick-change chuck body 3, and the inner side surface of the lower portion of the quick-change chuck sleeve 1 The inclined surface 101 is inclined downward and outward and contacts the ball 6. A receiving space 10 for receiving the return spring 5 is formed between the inner side surface of the upper part of the quick-change chuck sleeve 1 and the outer side surface of the quick-change chuck body 3. A quick-change chuck nut 2 for compressing the return spring 5 is provided on the outer side of the quick-change chuck body 3 above the return spring 5. The return spring 5 is compressed and used to apply pressure to the quick-change chuck sleeve 1, so that the inclined surface 101 moves downward and separates from the ball 6, and the upper end of the inclined surface 101 squeezes the ball 6 into the clamping hole 801, and the lower end of the quick-change chuck sleeve 1 abuts against the chuck platform 301. The ball 6 is a steel ball.

[0027] In this way, before the tail of the hollow drill 8 is inserted into the insertion hole of the quick-change chuck body 3, the quick-change chuck nut 2 is not screwed on the outside of the quick-change chuck body 3, the reset spring 5 is in a naturally extended state, the inclined surface 101 of the quick-change chuck sleeve 1 contacts the ball 6, and the ball 6 is on the outside of the accommodating through hole 302. When the hollow drill 8 needs to be locked, the tail of the hollow drill 8 is inserted into the insertion hole of the quick-change chuck body 3, wherein the accommodating through hole 302 corresponds to the clamping hole 801 of the tail of the hollow drill 8. By screwing the quick-change chuck nut 2 The quick-change chuck body 3 is connected to the outside of the quick-change chuck body 3 and the corresponding pressure is provided to the reset spring 5 by adjusting the number of rotations of the quick-change chuck nut 2. The reset spring 5 is compressed and applies downward pressure to the quick-change chuck sleeve 1, so that the inclined surface 101 of the quick-change chuck sleeve 1 moves downward and separates from the ball 6, and the upper end of the inclined surface 101 squeezes the ball 6 to the inner side of the accommodating through hole 302 and the clamping hole 801, and the lower end of the quick-change chuck sleeve 1 abuts against the chuck platform 301, so that the hollow drill 8 and the quick-change chuck body 3 are locked. Figure 1 , and the hollow drill 8 is driven by the power shaft 9 to perform the drilling action; when the hollow drill 8 needs to be unlocked, the operator pulls up the quick-change chuck sleeve 1 and moves the inclined surface 101 upward, the upper end of the inclined surface 101 is separated from the ball 6, and the ball 6 withdraws from the clamping hole 801 due to the loss of squeezing force and retreats to the outside of the accommodating through hole 302, so that the ball 6 is separated from the clamping hole 801, as shown in FIG. Figure 2 , the operator pulls out the hollow drill 8 downward to unlock the hollow drill 8 and the quick-change chuck body 3; therefore, the hollow drill 8 can be replaced conveniently and quickly without the aid of tools, and the efficiency of replacing the hollow drill 8 is high, thereby speeding up the drilling speed.

[0028] In one embodiment, the quick-change chuck body 3 is cylindrical, and a buffer gasket 4 is provided on the top surface of the chuck platform 301. When the hollow drill 8 is unlocked, the quick-change chuck sleeve 1 is pulled up to further compress the reset spring 5. After the hollow drill 8 is pulled out, the quick-change chuck sleeve 1 is released, and the reset spring 5 is extended and reset and exerts a downward force on the quick-change chuck sleeve 1. The quick-change chuck sleeve 1 moves downward under the downward force of the reset spring 5 and its own gravity and hits the buffer gasket 4 of the chuck platform 301. The setting of the buffer gasket 4 can play a buffering role on the quick-change chuck sleeve 1, reduce the impact force of the quick-change chuck sleeve 1 on the quick-change chuck body 3 when the reset spring 5 is reset, and improve the life of the quick-change chuck sleeve 1 and the quick-change chuck body 3 and reduce noise.

[0029] In one embodiment, the upper portion of the quick-change chuck body 3 is sleeved on the outer side of the power shaft 9 and is threadedly connected to the power shaft 9. A plurality of anti-loosening screws 7 are inserted on the upper side wall of the quick-change chuck body 3 and abut against the side of the power shaft 9. In this way, the quick-change chuck body 3 can be conveniently and firmly installed on the power shaft 9.

[0030] In one embodiment,

[0031] The lower inner side surface and the upper inner side surface of the quick-change chuck sleeve 1 are connected via a horizontal pressing surface 102 , and the lower end of the reset spring 5 abuts against the pressing surface 102 and the upper end abuts against the lower end surface of the quick-change chuck nut 2 .

[0032] Among them, the inner side surface of the quick-change chuck sleeve 1 below the clamping surface 102 includes a lower pressure surface 103, an inclined surface 101 and an upper pressure surface 104 from bottom to top. The lower pressure surface 103, the upper pressure surface 104 and the inner side surface of the quick-change chuck sleeve 1 above the clamping surface 102 are all vertical cylindrical surfaces, and the inclined surface 101 is a conical surface with the cone tip facing downward. When the hollow drill 8 needs to be locked, the upper end of the inclined surface 101 of the quick-change chuck sleeve 1 squeezes the ball 6 to the inner side of the accommodating through hole 302 and the clamping hole 801. Specifically, the upper pressure surface 104 at the upper end of the inclined surface 101 in the quick-change chuck sleeve 1 squeezes the ball 6 to the inner side of the accommodating through hole 302 and the clamping hole 801. The setting of the upper pressure surface 104 can increase the extrusion contact area with the ball 6, and the pressure on the ball 6 is relatively small.

[0033] The inner side surface of the quick-change chuck sleeve 1 on the upper side of the pressing surface 102 is located on the outer side of the quick-change chuck nut 2. Preferably, the inner diameter of the quick-change chuck sleeve 1 on the upper side of the pressing surface 102 matches the outer diameter of the quick-change chuck nut 2. In this way, when the hollow drill 8 is unlocked, the upper end of the quick-change chuck sleeve 1 can move to a position above the lower end of the quick-change chuck nut 2 during the process of the quick-change chuck sleeve 1 being pulled up.

[0034] In one embodiment, there are multiple accommodating through holes 302 and they are all in a frustum shape, the small diameter end of each accommodating through hole 302 is on the inner side of the quick-change chuck body 3, there are multiple clamping holes 801 and they are all in a cone shape, the cone tip of each clamping hole 801 faces the inner side of the tail of the hollow drill 8, and each accommodating through hole 302 corresponds to the position of the corresponding clamping hole 801. Preferably, the multiple accommodating through holes 302 are evenly distributed on the side wall of the quick-change chuck body 3 at the insertion hole.

[0035] The working principle of the utility model is:

[0036] Before the tail of the hollow drill 8 is inserted into the insertion hole of the quick-change chuck body 3, the quick-change chuck nut 2 is not screwed onto the outside of the quick-change chuck body 3, the reset spring 5 is in a naturally extended state, the inclined surface 101 of the quick-change chuck sleeve 1 contacts the ball 6, and the ball 6 is on the outside of the accommodating through hole 302. When the hollow drill 8 needs to be locked, the tail of the hollow drill 8 is inserted into the insertion hole of the quick-change chuck body 3, wherein the accommodating through hole 302 corresponds to the clamping hole 801 of the tail of the hollow drill 8. By screwing the quick-change chuck nut 2 onto the outside of the quick-change chuck body 3 and By adjusting the number of rotations of the quick-change chuck nut 2 to provide corresponding pressure on the reset spring 5, the reset spring 5 is compressed and applies downward pressure to the quick-change chuck sleeve 1, so that the inclined surface 101 of the quick-change chuck sleeve 1 moves downward and separates from the ball 6, and the upper end of the inclined surface 101 squeezes the ball 6 to the inner side of the accommodating through hole 302 and the clamping hole 801, and the lower end of the quick-change chuck sleeve 1 abuts against the chuck platform 301, so that the hollow drill 8 and the quick-change chuck body 3 are locked, and the hollow drill 8 is driven by the power shaft 9 to perform a drilling action;

[0037] When the hollow drill 8 needs to be unlocked, the operator pulls up the quick-change chuck sleeve 1 and moves the inclined surface 101 upward, the upper end of the inclined surface 101 is separated from the ball 6, and the ball 6 withdraws from the clamping hole 801 due to the loss of extrusion force and retreats to the outside of the accommodating through hole 302, so that the ball 6 is separated from the clamping hole 801, and the operator pulls out the hollow drill 8 downward to unlock the hollow drill 8 and the quick-change chuck body 3. When unlocking the hollow drill 8, the quick-change chuck sleeve 1 is pulled up to further compress the reset spring 5. After the hollow drill 8 is pulled out, the quick-change chuck sleeve 1 is released, and the reset spring 5 is extended and reset and generates a downward force on the quick-change chuck sleeve 1. The quick-change chuck sleeve 1 moves downward under the downward force of the reset spring 5 and its own gravity and hits the buffer gasket 4 of the chuck platform 301. The setting of the buffer gasket 4 can play a buffering role on the quick-change chuck sleeve 1.

[0038] Before locking the hollow drill 8 next time, first remove the quick-change chuck nut 2, then pull up the quick-change chuck sleeve 1 and make the inclined surface 101 of the quick-change chuck sleeve 1 contact the ball 6, wherein the ball 6 is located on the outside of the accommodating through hole 302, and then follow the above-mentioned operating steps for locking the hollow drill 8 to achieve locking of the hollow drill 8 and the quick-change chuck body 3.

[0039] In summary, the utility model can replace the hollow drill 8 conveniently and quickly without the aid of tools, and the replacement of the hollow drill 8 is simpler and more efficient, thereby speeding up the drilling speed; for reset springs 5 ​​of different specifications, it can provide a stable locking force for the hollow drill 8, and can provide a stable torque for the hollow drill 8; in addition, for reset springs 5 ​​of the same specification, according to the required maximum torque of the hollow drill 8, by adjusting the number of rotations of the quick-change chuck nut 2, the required maximum torque of the hollow drill 8 can be set to increase the life of the hollow drill 8.

[0040] The above are only preferred implementations of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. A quick-change device for replacing a hollow drill, characterized in that: The quick-change chuck body (3) comprises a quick-change chuck body (3), the upper part of which is mounted on a power shaft (9) and the lower part of which is provided with a socket for inserting a hollow drill (8), the lower end of which extends outward to form a chuck platform (301), the side wall of which is provided with a receiving through hole (302) for accommodating a ball (6), the receiving through hole (302) corresponding to the clamping hole (801) of the hollow drill (8), and the quick-change chuck body (3) is provided with a receiving through hole (302) for accommodating a ball (6). A quick-change chuck sleeve (1) is sleeved on the outside of the chuck body (3); the inner side surface of the lower part of the quick-change chuck sleeve (1) is an inclined surface (101) in contact with the ball (6); an accommodating space (10) for accommodating a reset spring (5) is formed between the inner side surface of the upper part of the quick-change chuck sleeve (1) and the outer side surface of the quick-change chuck body (3); and a quick-change chuck nut (2) for compressing the reset spring (5) is provided on the outer side of the quick-change chuck body (3) above the reset spring (5).

2. The quick-change device for replacing a hollow drill according to claim 1, characterized in that: The quick-change chuck body (3) is cylindrical in shape, and a buffer gasket (4) is provided on the top surface of the chuck platform (301).

3. The quick-change device for replacing a hollow drill according to claim 2, characterized in that: The upper part of the quick-change chuck body (3) is sleeved on the outer side of the power shaft (9) and is threadedly connected to the power shaft (9).

4. The quick-change device for replacing a hollow drill according to claim 3, characterized in that: A plurality of anti-loosening screws (7) abutting against the side surface of the power shaft (9) are inserted on the upper side wall of the quick-change chuck body (3).

5. The quick-change device for replacing a hollow drill according to claim 1, characterized in that: The lower inner side surface and the upper inner side surface of the quick-change chuck sleeve (1) are connected via a horizontal clamping surface (102); the lower end of the reset spring (5) abuts against the clamping surface (102) and the upper end abuts against the lower end surface of the quick-change chuck nut (2).

6. The quick-change device for replacing a hollow drill according to claim 5, characterized in that: The inner side surface of the quick-change chuck sleeve (1) below the clamping surface (102) comprises, from bottom to top, a lower pressing surface (103), an inclined surface (101) and an upper pressing surface (104); the lower pressing surface (103), the upper pressing surface (104) and the inner side surface of the quick-change chuck sleeve (1) above the clamping surface (102) are all vertical cylindrical surfaces; the inclined surface (101) is a conical surface with the cone tip facing downward.

7. The quick-change device for replacing a hollow drill according to claim 5, characterized in that: The inner side surface of the quick-change chuck sleeve (1) on the upper side of the pressing surface (102) is located on the outer side of the quick-change chuck nut (2).

8. The quick-change device for replacing a hollow drill according to claim 1, characterized in that: There are multiple accommodating through holes (302) and they are all in the shape of a cone. The small diameter end of each accommodating through hole (302) is located on the inner side surface of the quick-change chuck body (3). There are multiple clamping holes (801) and they are all in the shape of a cone. The cone tip of each clamping hole (801) faces the inner side surface of the tail of the hollow drill (8). Each accommodating through hole (302) corresponds to the position of the corresponding clamping hole (801).

9. The quick-change device for replacing a hollow drill according to claim 8, characterized in that: The plurality of accommodating through holes (302) are evenly distributed on the side wall of the quick-change chuck body (3) at the insertion hole.

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