CN113274092A

CN113274092A - Electric skull drill with automatic stop and limit functions

Info

Publication number: CN113274092A
Application number: CN202110575359.1A
Authority: CN
Inventors: 贺玉婷
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-05-26
Filing date: 2021-05-26
Publication date: 2021-08-20

Abstract

The invention belongs to the field of medical appliances, and particularly relates to an electric skull drill with an automatic stop and limit function, which comprises: the skull drill comprises an arc-shaped electric track frame, a ball screw sliding table and a skull drill body, wherein the ball screw sliding table is arranged at the working end of the arc-shaped electric track frame, the skull drill body is arranged at the working end of the ball screw sliding table along the radial direction, the skull drill body comprises a shell, a driving box, a gearbox, a chuck and a drill bit, and a torque detection assembly, wherein the torque detection assembly is arranged in the shell, is coaxially and fixedly connected with the gearbox, and has an output end coaxially and fixedly connected with the chuck; the telescopic rods and the drill bit are coaxially, slidably and uniformly distributed at the working end of the shell; the locking assembly is coaxially arranged on an output shaft of the gearbox. The skull drill can stop working at the moment of penetrating through the cartilaginous substances, can avoid the problem that the static drill bit punctures the meninges due to abutting inertia, and reduces the occurrence of medical accidents.

Description

Electric skull drill with automatic stop and limit functions

Technical Field

The invention belongs to the field of medical instruments, and particularly relates to an electric skull drill with an automatic stop and limiting function.

Background

Diseases such as intracranial pressure increase, craniocerebral injury, intracranial tumors, cerebrovascular diseases, intracranial infection and the like are one of killers which are harmful to human life and health for a long time. Brain surgery is an important means for curing the diseases, the primary principle in the surgery is to preserve nerve tissues and reduce side injury and infection, and the operation power device plays a key role in the brain surgery. The operation power device is a surgical operation device which can provide power, control and operation instruments required by an operation, reduce the working strength of doctors and realize accurate operation.

The outer layer of human brain is covered by hair and skin, the skull with protection function is arranged under the scalp, the dura mater is arranged under the skull, and because the dura mater has elasticity, a gap of nearly 2mm is still arranged between the skull and the dura mater after the skull is drilled through. When drilling the skull, medical personnel must carefully use the drilling tool, and the meninges cannot be drilled when the skull is drilled, so that the brain tissue is prevented from being injured, and the life safety of a patient is prevented from being endangered. When the skull drills, the skull drill is fed at a certain initial speed, when the skull drill just starts to drill a hole (first layer of hard bone), the resistance of the skull drill is increased, the rotating speed of a motor needs to be increased, when the skull drill penetrates through the hard bone layer and enters the middle layer (cartilaginous bone) of a person, the resistance of the skull drill is smaller than that of the first layer, the rotating speed of the motor needs to be reduced, the feeding force is reduced, and the skull is prevented from being instantaneously injured by drilling the skull and the meninges. However, the existing skull drill is stopped by judging by the experience and hand feeling of an operator, the error risk is extremely high, and the drill bit often damages the dura mater and even penetrates into the brain function central region, so that serious surgical accidents with high death rate are caused.

Disclosure of Invention

In order to solve the technical problem, an electric skull drill with an automatic stop and limit function is provided.

In order to achieve the above purposes, the technical scheme adopted by the invention is as follows:

an electric skull drill with an automatic stop limiting function comprises an arc-shaped electric track frame, a ball screw sliding table and a skull drill body, wherein the ball screw sliding table is arranged at the working end of the arc-shaped electric track frame along the radial direction;

the device also comprises a torque detection assembly, a telescopic rod and a locking assembly;

the torque detection assembly is arranged in the shell, the input end of the torque detection assembly is coaxially and fixedly connected with the output end of the gearbox, the output end of the torque detection assembly is coaxially and fixedly connected with the chuck, and the torque detection assembly is electrically connected with a controller;

the telescopic rod slides in the same direction as the drill bit, the outer end of the telescopic rod is flush with the front end of the drill bit, and the circumferential surface of the telescopic rod is provided with limit grooves at equal intervals along the axial direction;

the locking component is coaxially arranged on the output shaft of the gearbox and comprises a locking component,

the fixing disc and the fixing cylinder are coaxially and fixedly arranged on an output shaft of the gearbox, the fixing cylinder is positioned on one side of the fixing disc, and a fixing edge is arranged at one end of the outer circumferential surface of the fixing cylinder;

the rotating disc and the limiting ring are coaxially and fixedly arranged on the fixed cylinder, and the rotating disc is positioned between the fixed edge and the limiting ring;

the torsional spring is coaxially sleeved on the fixed cylinder, and two ends of the torsional spring are respectively and fixedly connected with the opposite ends of the fixed edge and the rotating disc;

the U-shaped frame is circumferentially and fixedly arranged on one side of the fixed disc;

the first connecting rod is arranged on the U-shaped frame in a sliding manner along the radial direction of the fixed disc;

one end of the second connecting rod is hinged with one end of the first connecting rod facing the axis of the fixed disc, and the other end of the second connecting rod is hinged with the outer side of the rotating disc;

the arc, the arc is along the radial fixed setting of fixed disk at the other end of first connecting rod, and the arc is coaxial with the fixed disk, and is provided with spacing edge on the outer periphery of arc, spacing edge can along radial joint in the spacing groove.

Preferably, the controller is provided with a torque threshold range, when the torque value detected by the torque detection assembly is not in the threshold range, the controller controls the driving box to stop working, the gearbox stops synchronously, and the locking assembly locks the telescopic rod so that the telescopic rod cannot slide in the machine shell along the axial direction.

Preferably, still including the butt circle, butt circle and the coaxial axial fixed connection of telescopic link, and the butt circle is coaxial with the drill bit, the outer end of butt circle and the drill bit drill end parallel and level.

Preferably, a flexible ring is further included, the flexible ring being coaxially disposed at the abutment end of the abutment ring.

Preferably, the butt end of butt ring is provided with the settling ring groove coaxially, and the groove depth of settling ring groove is less than the width of flexible ring, and flexible ring is coaxial to be set up in settling ring groove, and the outside of settling ring groove still is provided with the tooth along coaxially, and the tooth is along being used for preventing that flexible ring breaks away from settling ring groove.

Preferably, the device also comprises a movable connecting assembly, the movable connecting assembly is uniformly distributed at one end of the abutting ring along the axial direction, the telescopic rod is coaxially and detachably connected with the movable connecting assembly, the movable connecting assembly comprises a connecting rod,

the external thread fixing cylinders are uniformly distributed at one end of the abutting ring along the axial direction, the external diameter of each external thread fixing cylinder is gradually increased from a fixed end to the outer end, the external thread fixing cylinders are uniformly distributed with slots along the axial direction, and one end of the telescopic rod is coaxially inserted into the external thread fixing cylinders;

and the inner diameter of the adjusting nut is gradually reduced from one end facing the abutting ring to the other end, and the adjusting nut is coaxially screwed on the external thread fixing cylinder.

Preferably, the device also comprises a resetting installation part, the resetting installation part is arranged in the shell, one end of the telescopic rod is coaxially arranged on the resetting installation part, the resetting installation part needs to overcome the elasticity and enter the shell, the resetting installation part comprises,

the telescopic rod is coaxially and slidably arranged on the first fixing lug and the second fixing lug;

the fixing ring is coaxially arranged on the telescopic rod, is positioned between the first fixing lug and the second fixing lug and is coaxially screwed on the telescopic rod;

the spring is coaxially sleeved on the telescopic rod, and two ends of the spring are respectively abutted to opposite ends of the first fixing lug and the fixing ring.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the invention, the skull drill can stop working at the moment of penetrating through the cartilaginous bone through the torque detection assembly, the telescopic rod and the locking assembly, so that the situation that the drill bit punctures the meninges due to abutting inertia is avoided; or the drill bit stops working instantly when clamping the main craniotomy point, so that the situation that the peripheral side of the craniotomy point is cracked due to overlarge torsion is avoided;

2. according to the invention, the abutting ring which can be coaxially abutted against the outer side of the craniotomy point can facilitate accurate and coaxial hole opening of the drill bit;

3. the flexible ring can weaken the vibration force transmitted to the skull by the skull drill body through the telescopic rod and the abutting ring, thereby reducing the occurrence of accidents;

4. according to the invention, one end of the telescopic rod can elastically slide in the shell through the spring, so that the telescopic rod can reset after craniotomy is finished.

Drawings

FIG. 1 is a perspective view of the present invention;

FIG. 2 is a side view of the present invention;

FIG. 3 is a cross-sectional view at section B-B of FIG. 2;

FIG. 4 is a perspective cross-sectional view at section B-B of FIG. 2;

FIG. 5 is an enlarged view of a portion of FIG. 3 at C;

FIG. 6 is a perspective view of the transmission and latch assembly of the present invention;

FIG. 7 is an exploded perspective view of the transmission and latch assembly of the present invention;

FIG. 8 is an enlarged view of a portion of the present invention at D of FIG. 3;

FIG. 9 is a perspective view of the interference ring and articulating assembly of the present invention;

fig. 10 is a partial enlarged view of the invention at E of fig. 3.

The reference numbers in the figures are:

a1-case; a2-handle; a3-drive box; a4-gearbox; a5-switch; a6-clamp; a 7-drill bit;

1-a torque detection assembly;

2, a telescopic rod; 2 a-a limit groove;

3-a locking assembly; 3 a-fixing disc; 3 b-a fixed cylinder; 3b 1-stationary edge; 3 c-a rotating disc; 3 d-a spacing ring; a3 eU-shaped frame; 3 f-a first link; 3 g-a second link; 3 h-arc plate; 3h 1-stop edge; 3 i-torsion spring;

4-a butt ring; 4 a-arranging a ring groove; 4a 1-edge of tooth;

5-a flexible ring;

6-a movable connection assembly; 6 a-an external thread fixing cylinder; 6a 1-slotted; 6 b-adjusting the nut;

7-a reduction mount; 7 a-a first fixing lug; 7 b-a second fixing lug; 7 c-a retaining ring; 7 d-spring.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.

As shown in fig. 1-7, an electric skull drill with self-stop and spacing functions comprises an arc-shaped electric track frame, a ball screw sliding table and a skull drill body, wherein the ball screw sliding table is radially arranged at the working end of the arc-shaped electric track frame, the skull drill body is radially arranged at the working end of the ball screw sliding table along the arc-shaped electric track frame, and the skull drill body comprises a machine shell a1, a driving box A3, a gearbox a4, a chuck a6 and a drill bit a 7;

specifically, the arc-shaped electric track frame is arranged at the pillow part of the operating bed, so that the ball screw sliding table can move along the circumferential direction of the arc-shaped electric track frame at the pillow part, and the ball screw sliding table is started, so that the skull drill body can move towards the head of a patient along the radial direction; the driving box A3 is started to enable the output end of the driving box A3 to output torque to the gearbox A4, so that the torque is output to the chuck A6 from the output end of the gearbox A4, namely, the chuck A6 can drive the drill bit A7 to rotate; housing a1 is used to support and mount drive housing A3, transmission a4 and chuck a6, by which chuck a6 different types of drills a7 can be replaced.

The electric skull drill also comprises a power-driven skull drill,

the torque detection assembly 1 is arranged in the casing A1, the input end of the torque detection assembly 1 is coaxially and fixedly connected with the output end of the gearbox A4, the output end of the torque detection assembly 1 is coaxially and fixedly connected with the chuck A6, and the torque detection assembly is electrically connected with a controller (not shown in the figure);

the telescopic rod 2, the telescopic rod 2 and the drill bit A7 are coaxially, slidably and uniformly distributed at the working end of the machine shell A1, the outer end of the telescopic rod 2 is flush with the front end of the drill bit A7, and the circumferential surface of the telescopic rod is provided with limiting grooves 2a at equal intervals along the axial direction;

a locking assembly 3, the locking assembly 3 is coaxially arranged on the output shaft of the gearbox A4, and comprises,

the fixing disc 3a and the fixing cylinder 3b are coaxially and fixedly arranged on an output shaft of the gearbox A4, the fixing cylinder 3b is positioned on one side of the fixing disc 3a, and one end of the outer circumferential surface of the fixing cylinder 3b is coaxially provided with a fixing edge 3b 1;

the rotating disc 3c and the limiting ring 3d are coaxially and rotatably arranged on the fixed cylinder 3b, and the rotating disc 3c is positioned between the fixed edge 3b1 and the limiting ring 3 d;

the torsion spring 3i is coaxially sleeved on the fixed cylinder 3b, and two ends of the torsion spring 3i are respectively and fixedly connected with opposite ends of the fixed edge 3b1 and the rotating disc 3 c;

the U-shaped frame 3e is circumferentially and fixedly arranged on one side of the fixed disc 3 a;

the first connecting rod 3f is arranged on the U-shaped frame 3e in a manner of sliding along the radial direction of the fixed disc 3 a;

one end of the second connecting rod 3g is hinged with one end of the first connecting rod 3f facing to the axis of the fixed disc 3a, and the other end of the second connecting rod 3g is hinged with the outer side of the rotating disc 3 c;

arc 3h, arc 3h set up the other end at first connecting rod 3f along the radial fixed of fixed disk 3a, and arc 3h is coaxial with fixed disk 3a, and is provided with spacing along 3h1 on the outer periphery of arc 3h, spacing along under gearbox A4 operating condition, can along radial joint in spacing groove 2 a.

Specifically, when a hole is opened, the drill bit A7 is aligned to a craniotomy point, and the telescopic rods 2 and the drill bit A7 are coaxially and uniformly abutted to the outer side of the craniotomy point; the ball screw slide is activated so that the rotating drill bit a7 abuts against the craniotomy point to drill a hole, while the locking assembly 3 releases the telescopic rod 2 inside the housing a1 so that the telescopic rod 2 can slide towards the inside of the housing a 1.

When the driving box A3 drives the gearbox A4 to work, the output shaft of the gearbox A4 drives the fixed disc 3a and the fixed cylinder 3b to coaxially rotate, and the fixed edge 3b1 and the limiting ring 3d can prevent the rotating disc 3c from axially separating from the fixed cylinder 3 b; the torsion spring 3i is coaxially sleeved on the fixed cylinder 3b, two ends of the torsion spring 3i are respectively and fixedly connected with opposite ends of the fixed edge 3b1 and the rotating disc 3c, so that the fixed edge 3b1 can drive the rotating disc 3c to synchronously rotate through the torsion spring 3i, the rotating disc 3c rotates at a speed slower than that of the fixed cylinder 3b due to torsion generated by deformation of the torsion spring 3i, the rotating disc 3c further pulls one end of the second connecting rod 3g under the action of centrifugal force, and the other end of the second connecting rod 3g pulls one end of the first connecting rod 3f to be close to the axis of the fixed disc 3a along the radial direction, so that the torsion spring 3i can withdraw from the limiting groove 2a, namely the telescopic rod 2 can slide in the casing A1 along the axial direction;

the controller is provided with a torque threshold range, when the torque value detected by the torque detection assembly is not in the threshold range, the controller controls the driving box A3 to stop working, when the driving box A3 is closed, the gearbox A4 stops working, the fixed disc 3a and the fixed cylinder 3b are synchronously static, and the torsion spring 3i recovers deformation, namely the rotating disc 3c is reset relative to the fixed cylinder 3b, namely the rotating disc 3c pushes one end of the second connecting rod 3g, so that the first connecting rod 3f deviates from the axis of the fixed disc 3a along the radial direction, the limiting edge 3h1 can be clamped in the limiting groove 2a along the radial direction, namely the locking assembly 3 locks the telescopic rod 2 to enable the telescopic rod to not slide in the machine shell A1 along the axial direction.

The controller is arranged on the back side of the casing A1, the torque detection assembly 1 is electrically connected with the controller, a torque threshold range can be preset through the controller, and when the detected torque value of the torque detection assembly 1 is within the range, the rotary drill A7 can sequentially penetrate through the hard bone layer and the cartilaginous bone; when the torque value detected by the torque detection assembly 1 is smaller than the range value, the situation that the rotary drill bit A7 penetrates through the cartilage layer is indicated, the controller immediately closes the driving box A3, and meanwhile, the locking assembly 3 locks the telescopic rod 2, as the outer end of the telescopic rod 2 abuts against the outer side of the craniotomy point, namely the chuck A6 cannot continuously abut against the craniotomy point under the inertia effect, the static drill bit A7 is prevented from puncturing the meninges under the inertia effect; when the torque value detected by the torque detection component 1 is larger than the threshold range value, it is indicated that the output torque of the skull drill body is smaller than the torque required for drilling, or the rotary drill bit a7 is clamped at the craniotomy point, the controller is also required to immediately close the driving box A3, and meanwhile, the locking component 3 locks the telescopic rod 2, because the outer end of the telescopic rod 2 is abutted against the outer side of the craniotomy point, namely, the chuck a6 cannot continuously abut against the craniotomy point under the inertia effect, the situation that the periphery of the craniotomy point is cracked due to overlarge torque force under the inertia effect is further prevented, and medical accidents are avoided.

As shown in fig. 1 and 8, the telescopic rod further comprises an abutting ring 4, the abutting ring 4 is fixedly connected with the telescopic rod 2 in the same axial direction, the abutting ring 4 is coaxial with the drill bit a7, and the outer end of the abutting ring 4 is flush with the drill end of the drill bit a 7. The outer end of the telescopic rod 2 is provided with the abutting ring 4 which is coaxial with the drill bit A7, so that the abutting ring 4 can be coaxially abutted to the outer side of the craniotomy point, the stress area is increased, and the ball screw sliding table drives the skull drill body to drill holes in the direction coaxial with the craniotomy point; by the abutment ring 4 being able to coaxially abut outside the craniotomy point, accurate coaxial trepanning of the drill bit a7 can be facilitated.

Further, still include flexible ring 5, flexible ring 5 sets up the butt end at butt circle 4 with the same axle. When the abutting ring 4 is coaxially abutted to the skull opening point, the abutting ring 4 can be prevented from being directly abutted to the skull through the flexible ring 5, and the vibration force conducted to the skull by the skull drill body is weakened, so that medical accidents can be further caused.

Further, the abutting end of the abutting ring 4 is coaxially provided with a mounting ring groove 4a, the groove depth of the mounting ring groove 4a is smaller than the width of the flexible ring 5, the flexible ring 5 is coaxially arranged in the mounting ring groove 4a, the outer side of the mounting ring groove 4a is also coaxially provided with a tooth edge 4a1, and the tooth edge 4a1 is used for preventing the flexible ring 5 from being separated from the mounting ring groove 4 a. The depth of the placement ring groove 4a is smaller than the width of the flexible ring 5, when the flexible ring 5 is coaxially arranged in the placement ring groove 4a, the flexible ring 5 deforms, the outer end of the flexible ring exceeds the abutting end of the abutting ring 4, the abutting ring 4 is prevented from directly abutting against the skull, the tooth edge 4a1 can prevent the flexible ring 5 from axially separating from the placement ring groove 4a, the flexible ring 5 is prevented from axially separating from the placement ring groove 4a during craniotomy, and the flexible ring 5 can be deformed to separate from the placement ring groove 4a during cleaning;

as shown in fig. 9, the utility model also comprises a movable connecting component 6, the movable connecting component 6 is evenly distributed at one end of the abutting ring 4 along the axial direction, the telescopic rod 2 is coaxially and detachably connected with the movable connecting component 6, the movable connecting component 6 comprises,

the external thread fixing cylinders 6a are uniformly distributed at one end of the abutting ring 4 along the axial direction, the outer diameter of each external thread fixing cylinder 6a is gradually increased from the fixed end to the outer end, the external thread fixing cylinders 6a are uniformly distributed with slots 6a1 along the axial direction, and one end of the telescopic rod 2 is coaxially inserted into the external thread fixing cylinders 6 a;

and an adjusting nut 6b, wherein the inner diameter of the adjusting nut 6b is gradually reduced from one end to the other end of the abutting ring 4, and the adjusting nut 6b is coaxially screwed on the external thread fixing cylinder 6 a.

Specifically, the adjusting nut 6b is coaxially screwed on one end of the external thread fixing cylinder 6a facing the abutting ring 4 in advance, that is, the inside of the external thread fixing cylinder 6a is not smaller than the diameter of the telescopic rod 2, one end of the telescopic rod 2 is coaxially inserted in the external thread fixing cylinder 6a, and the adjusting nut 6b is coaxially rotated, so that the adjusting nut 6b deviates from the abutting ring 4, because the outer diameter of the external thread fixing cylinder 6a gradually increases from the fixed end to the outer end, and the inner diameter of the adjusting nut 6b gradually decreases from one end facing the abutting ring 4 to the other end, and the external thread fixing cylinder 6a is axially and uniformly provided with the slots 6a1, that is, the external thread fixing cylinder 6a can be radially inwardly deformed, that is, during the rotation of the adjusting nut 6b, the inner diameter of the external thread fixing cylinder 6a gradually decreases, that is, the external thread fixing cylinder 6a can coaxially with the telescopic rod 2, thereby fixedly connecting the telescopic rod 2 and the abutment ring 4.

As shown in fig. 3 and 10, the telescopic rod further comprises a resetting installation part 7, the resetting installation part 7 is arranged inside the machine shell a1, one end of the telescopic rod 2 is coaxially arranged on the resetting installation part 7, and the resetting installation part 7 needs to overcome the elasticity to enter the machine shell a 1. The reduction mounting member 7 is comprised of,

the first fixing lug 7a and the second fixing lug 7b are sequentially arranged inside the machine shell A1 along the axial direction of the drill A7, the second fixing lug 7b is positioned on one side, facing the drill A7, of the first fixing lug 7a, and the telescopic rod 2 is coaxially and slidably arranged on the first fixing lug 7a and the second fixing lug 7 b;

the fixing ring 7c is coaxially screwed on the telescopic rod 2, and the fixing ring 7c is positioned between the first fixing lug 7a and the second fixing lug 7 b;

the spring 7d is coaxially sleeved on the telescopic rod 2, and two ends of the spring 7d are respectively abutted against opposite ends of the first fixing lug 7a and the fixing ring 7 c.

One end of the telescopic rod 2 can elastically slide in the machine shell A1 through the spring 7d, so that the telescopic rod 2 is reset after craniotomy is finished; when assembling or repairing the skull drill body, the fixing ring 7c is rotated to facilitate the detachment of the telescopic rod 2 from the casing A1.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. The utility model provides an electronic skull bores with stop by oneself limit function, includes that the electronic track frame of arc, ball screw slip table and skull bore the body, and the ball screw slip table radially sets up the work end at the electronic track frame of arc, and the skull bores the body and radially sets up the work end at the ball screw slip table along the electronic track frame of arc, its characterized in that:

the skull drill body comprises a shell, a driving box, a gearbox, a chuck, a drill bit, a torque detection assembly, a telescopic rod and a locking assembly;

the telescopic rod and the drill bit slide in the same direction, the outer end of the telescopic rod is flush with the front end of the drill bit, and the circumferential surface of the telescopic rod is provided with limit grooves at equal intervals along the axial direction;

the locking subassembly coaxial setting is on the output shaft of gearbox, and it includes:

2. The electric skull drill with the self-stop limiting function according to claim 1, wherein the controller is provided with a torque threshold range, when the torque value detected by the torque detection assembly is not within the threshold range, the controller controls the driving box to stop working, the gearbox to stop synchronously, and the locking assembly locks the telescopic rod so that the telescopic rod cannot slide in the axial direction in the casing.

3. The electric skull drill with the automatic stop and limit function according to the claims 1-2, further comprising a butt ring, wherein the butt ring is fixedly connected with the telescopic rod in the same direction, the butt ring is coaxial with the drill bit, and the outer end of the butt ring is flush with the drilling end of the drill bit.

4. The electric skull drill with the automatic stop and limiting function according to the claims 1-3, characterized in that the electric skull drill further comprises a flexible ring, and the flexible ring is coaxially arranged at the abutting end of the abutting ring.

5. The electric skull drill with the self-stop limiting function is characterized in that the abutting end of the abutting ring is coaxially provided with a mounting ring groove, the groove depth of the mounting ring groove is smaller than the width of the flexible ring, the flexible ring is coaxially arranged in the mounting ring groove, and the outer side of the mounting ring groove is also coaxially provided with a tooth edge which is used for preventing the flexible ring from being separated from the mounting ring groove.

6. The electric skull drill with the automatic stop and limit function is characterized by further comprising movable connecting assemblies, wherein the movable connecting assemblies are uniformly distributed at one end of the abutting ring along the axial direction, the telescopic rods are coaxially and detachably connected with the movable connecting assemblies, each movable connecting assembly comprises a connecting rod,

the external thread fixing cylinders are uniformly distributed at one end of the abutting ring along the axial direction, the outer diameters of the external thread fixing cylinders are gradually increased from the fixed end to the outer end, the external thread fixing cylinders are uniformly distributed with slots along the axial direction, and one end of the telescopic rod is coaxially inserted in the external thread fixing cylinders;

the inner diameter of the adjusting nut is gradually reduced from one end facing the abutting ring to the other end, and the adjusting nut is coaxially screwed on the outer thread fixing cylinder.

7. The electric skull drill with the automatic stop and limiting function is characterized by further comprising a reset installation part, wherein the reset installation part is arranged inside the machine shell, and one end of the telescopic rod is coaxially arranged on the reset installation part; the reset installation component comprises a reset installation component,

the fixing ring is coaxially screwed on the telescopic rod and is positioned between the first fixing lug and the second fixing lug;