Safe medical craniotomy automatic stop drill bit
Through the design of the coupling sleeve assembly, the self-stop of the inner drill bit is achieved by using spring compression and rebound mechanisms, solving the safety and disassembly convenience of the existing self-stop drill bit, ensuring the safe operation and simple maintenance of the drill bit.
Patent Information
- Application Number
- CN202420990215.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-09
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2034-05-09
AI Technical Summary
When the ring spring retaining ring wears or takes off, there is a risk of separation of the internal and external drill bits, resulting in failure of operation and inconvenient disassembly.
The coupling sleeve assembly is adopted, including a coupling sleeve, a locking thimble, a spring, a spring seat and a steel ball structure. The self-stop of the inner drill bit is achieved through the compression and rebound mechanism of the spring, and the steel ball is used to fix the coupling sleeve and the shell, simplifying the disassembly process.
The inner drill bit stops itself after drilling through the skull, avoiding the outer drill bit from being released, improving safety and simplifying the disassembly and cleaning process of the drill bit.
Smart Images
Figure CN223041575U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a safer medical craniotomy self-stopping drill bit, belonging to the technical field of medical devices. Background Art
[0002] In neurosurgery, there is a craniotomy operation. As the name implies, a craniotomy is to open a hole in the skull. Before the craniotomy, three holes need to be drilled in the skull, and then the skull is cut by a wire saw or a cutting method, and then the operation is performed in the window area. A craniotomy drill bit is required for drilling in a craniotomy operation. The craniotomy drill bit has a self-stopping function, that is, when the inner drill bit penetrates the skull, the inner drill bit stops rotating to prevent the drill bit from touching the brain.
[0003] At present, the outer drill bit of the self-stopping drill bit is fixed by an annular spring retaining ring. When the annular spring retaining ring is worn or accidentally disengaged, the inner and outer drill bits of the self-stopping drill bit will be separated, posing a risk of failure during operation. Content of the Utility Model
[0004] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a safer medical craniotomy self-stopping drill bit. When the inner drill bit penetrates the skull, the axial force of the skull on the inner drill bit disappears or is less than a certain value. Under the action of the internal mechanism of the device, the torque is no longer transmitted to the inner drill bit, and the cutting torque of the inner drill bit is automatically cut off, so as to achieve the purpose of self-stopping of the inner drill bit after penetrating the skull without damaging others, and at the same time prevent the outer drill bit from coming off.
[0005] The safer medical craniotomy self-stopping drill bit described in the utility model includes a coupling sleeve assembly and a drill bit assembly. One end of the coupling sleeve assembly is inserted and assembled with the end of the output shaft of the electric drill, and the other end of the coupling sleeve assembly is sleeved and assembled with the drill bit assembly. The coupling sleeve assembly includes a connecting sleeve, a locking thimble, a spring, and a spring seat. The locking thimble is slidably inserted into the inner part of the connecting sleeve far from the drill bit assembly, and the spring seat is slidably inserted into the inner part of the connecting sleeve close to the drill bit assembly. The locking thimble and the spring seat are connected by a spring; the drill bit assembly includes an inner drill bit, an outer drill bit, and a housing. The housing is sleeved on the outer periphery of the connecting sleeve and the outer drill bit, the outer drill bit is sleeved on the outer periphery of the inner drill bit, internal threads are provided on the circumferential wall of the housing in contact with the outer drill bit, external threads are provided on the outer circumferential wall of the outer drill bit, and the housing and the outer drill bit are connected by threads.
[0006] The connecting sleeve is inserted and assembled with the end of the output shaft of the electric drill. When the drill bit is in the self-stop state, the ratchet wheel at the left end of the inner drill bit does not engage with the tooth groove at the right end of the connecting sleeve, and relative sliding occurs between the connecting sleeve and the housing, that is, the self-stop state. When the inner drill bit contacts the skull and receives an axial pressure, the pressure is transmitted to the spring, and the spring is compressed. At this time, the ratchet wheel on the upper edge of the inner drill bit engages with the tooth groove on the connecting sleeve, and the rotation of the connecting sleeve will drive the inner drill bit and the outer drill bit to rotate and cut together. When about to drill through the skull, the inner drill bit contacts the periosteum, and the supporting force of the periosteum is not enough to support the compression of the spring. The spring rebounds, and the inner drill bit pops out from the tooth groove of the connecting sleeve to achieve self-stop. The housing and the outer drill bit are connected by threads, which can effectively prevent the outer drill bit from coming off during operation.
[0007] An orifice snap ring is embedded on the inner wall of the connecting sleeve near one end of the inner drill bit. A perforation is axially opened in the middle of the orifice snap ring. The spring seat extends towards the inner drill bit direction and is provided with a protrusion, and the protrusion passes through the perforation. The orifice snap ring limits the spring seat to prevent the spring seat from passing through the connecting sleeve.
[0008] A number of tapered holes are circumferentially and evenly distributed on the circumferential wall of the connecting sleeve, and steel balls are assembled in the tapered holes.
[0009] A first arc groove is opened on the outer circumferential wall of the locking ejector pin, and a second arc groove is opened on the inner circumferential wall of the housing. Both the first arc groove and the second arc groove are matched with the convex surface of the steel ball.
[0010] The number of the tapered holes is at least three. The connecting sleeve and the housing are fixed by steel balls. When the locking ejector pin is pushed out by the spring, the locking ejector pin will squeeze the steel balls out of the connecting sleeve, and a part of the steel balls is stuck in the second arc groove on the housing. At this time, the overall structure is locked. To disassemble the drill bit assembly, only need to press the locking ejector pin from the left end so that the first arc groove on the locking ejector pin just falls on the convex arc surface of the steel ball. At this time, the steel balls move radially inwards, separating the housing and the connecting sleeve to achieve the purpose of disassembly and cleaning. Compared with the threaded locking structure, it has the advantage of simple operation, because over-tightening the thread requires tool assistance to unlock.
[0011] The outer drill bit is connected to the inner drill bit through a cylindrical pin.
[0012] Compared with the prior art, the beneficial effects of the present utility model are:
[0013] (1) When the drill bit is in the self-stop state, the ratchet wheel at the left end of the inner drill bit does not mesh with the tooth groove at the right end of the connecting sleeve, and relative sliding occurs between the connecting sleeve and the housing, that is, the self-stop state. When the inner drill bit contacts the skull and receives an axial pressure, the pressure is transmitted to the spring, and the spring is compressed. At this time, the ratchet wheel on the upper edge of the inner drill bit meshes with the tooth groove on the connecting sleeve, and the rotation of the connecting sleeve will drive the inner drill bit and the outer drill bit to rotate and cut together. When the skull is about to be drilled through, the inner drill bit contacts the periosteum, and the supporting force of the periosteum is not sufficient to support the compression of the spring. The spring rebounds, and the inner drill bit pops out from the tooth groove of the connecting sleeve to achieve self-stop. The housing and the outer drill bit are connected by threads, which can effectively prevent the outer drill bit from coming off during operation.
[0014] (2) The connecting sleeve and the housing are fixed by steel balls. When the locking thimble is pushed out by the spring, the locking thimble will squeeze the steel balls out of the connecting sleeve, and a part of the steel balls is stuck in the second arc groove on the housing. At this time, the overall structure is locked. To disassemble the drill bit assembly, just press the locking thimble from the left end so that the first arc groove on the locking thimble just falls on the protruding arc surface of the steel ball. At this time, the steel balls move radially inward, separating the housing from the connecting sleeve to achieve the purpose of disassembly and cleaning. Compared with the threaded locking structure, it has the advantage of simple operation, because over-tightening the thread requires the assistance of tools to unlock. Description of the Drawings
[0015] Figure 1 is a schematic diagram of the self-stop state of Embodiment 1 of the present utility model;
[0016] Figure 2 is Figure 1 the cross-sectional structure schematic diagram along the A-A direction in
[0017] Figure 3 is a schematic diagram of the working state of Embodiment 1 of the present utility model;
[0018] Figure 4 is Figure 3 the cross-sectional structure schematic diagram along the B-B direction in
[0019] In the figure: 1. Locking thimble; 2. Connecting sleeve; 3. Spring; 4. Steel ball; 5. Housing; 6. Hole retaining ring; 7. Cylindrical pin; 8. Outer drill bit; 9. Inner drill bit; 10. Protrusion; 11. Perforation; 12. Spring seat; 13. Second arc groove; 14. Taper hole; 15. First arc groove. Detailed Embodiments
[0020] The following further describes the present utility model in conjunction with embodiments:
[0021] Embodiment 1
[0022] As Figures 1 to 4As shown in the figure, a safer medical craniotomy self-stopping drill bit of the present utility model includes a coupling sleeve assembly and a drill bit assembly. One end of the coupling sleeve assembly is inserted and assembled with the end of the output shaft of the electric drill, and the other end of the coupling sleeve assembly is sleeved and assembled with the drill bit assembly. The coupling sleeve assembly includes a connecting sleeve 2, a locking thimble 1, a spring 3, and a spring seat 12. The locking thimble 1 is slidably inserted into the inner part of the connecting sleeve 2 away from the drill bit assembly, and the spring seat 12 is slidably inserted into the inner part of the connecting sleeve 2 close to the drill bit assembly. The locking thimble 1 and the spring seat 12 are connected by a spring 3. The drill bit assembly includes an inner drill bit 9, an outer drill bit 8, and a housing 5. The housing 5 is sleeved on the outer circumferences of the connecting sleeve 2 and the outer drill bit 8, the outer drill bit 8 is sleeved on the outer circumference of the inner drill bit 9, an internal thread is provided on the circumferential wall of the housing 5 in contact with the outer drill bit 8, an external thread is provided on the outer circumferential wall of the outer drill bit 8, and the housing 5 and the outer drill bit 8 are connected by threads.
[0023] A hole retaining snap ring 6 is embedded on the inner wall of the connecting sleeve 2 near one end of the inner drill bit 9. A perforation 11 is axially opened in the middle of the hole retaining snap ring 6. The spring seat 12 extends towards the inner drill bit 9 to set a protrusion 10, and the protrusion 10 passes through the perforation 11.
[0024] A plurality of tapered holes 14 are circumferentially and evenly arranged on the circumferential wall of the connecting sleeve 2, and steel balls 4 are assembled in the tapered holes 14.
[0025] A first arc groove 15 is opened on the outer circumferential wall of the locking thimble 1, and a second arc groove 13 is opened on the inner circumferential wall of the housing 5. Both the first arc groove 15 and the second arc groove 13 are matched with the protruding surfaces of the steel balls 4.
[0026] The number of the tapered holes 14 is three, and the number of the steel balls 4 is also three. When machining the tapered holes 14, drilling needs to start from the connecting sleeve 2 opposite to the tapered holes 14 to be machined, and the steel balls are also loaded into the tapered holes 14 from the opposite machining holes.
[0027] The outer drill bit 8 is connected to the inner drill bit 9 by a cylindrical pin 7.
[0028] Working process: When the drill bit is in the self-stopping state, as Figure 3 shown, the ratchet wheel at the left end of the inner drill bit 9 is not engaged with the tooth groove at the right end of the connecting sleeve 2, and relative sliding occurs between the connecting sleeve 2 and the housing 5, that is, the self-stopping state. When the inner drill bit 9 contacts the skull and receives an axial pressure, the pressure is transmitted to the spring 3, and the spring 3 is compressed. As Figure 4 shown, at this time, the ratchet wheel on the upper edge of the inner drill bit 9 is engaged with the tooth groove on the connecting sleeve 2, and the rotation of the connecting sleeve 2 will drive the inner drill bit 9 and the outer drill bit 8 to rotate and cut together. When about to drill through the skull, the inner drill bit 9 contacts the periosteum, and the supporting force of the periosteum is not enough to support the compression of the spring 3. The spring 3 rebounds, and the inner drill bit 9 pops out from the tooth groove of the connecting sleeve 2 to achieve self-stopping.
[0029] In the present utility model, the description of the directions and relative positional relationships of the structures, such as the descriptions of front, back, left, right, up, and down, does not constitute a limitation to the present utility model and is only for convenience of description.
Claims
1. A safer medical craniotomy self-stop drill, characterized in that: The invention comprises a connecting sleeve assembly and a drill assembly, wherein one end of the connecting sleeve assembly is plugged and assembled with the output shaft end of the electric drill, and the other end of the connecting sleeve assembly is sleeved and assembled with the drill assembly, wherein the connecting sleeve assembly comprises a connecting sleeve (2), a locking ejector pin (1), a spring (3), and a spring seat (12), wherein the connecting sleeve (2) is slidably inserted with the locking ejector pin (1) in the interior away from the drill assembly, and the connecting sleeve (2) is slidably inserted with the spring seat (12) in the interior close to the drill assembly, and the locking ejector pin (1) and the spring seat (12) are connected via the spring (3); the drill assembly comprises an inner drill bit (9), an outer drill bit (8), and an outer shell (5), wherein the outer shell (5) is sleeved on the outer circumference of the connecting sleeve (2) and the outer drill bit (8), and the outer drill bit (8) is sleeved on the outer circumference of the inner drill bit (9), an inner thread is arranged on the circumferential wall of the outer shell (5) in contact with the outer drill bit (8), and an outer thread is arranged on the outer circumferential wall of the outer drill bit (8), and the outer shell (5) and the outer drill bit (8) are connected via threads.
2. The safer medical craniotomy self-stopping drill according to claim 1 is characterized in that: A hole elastic retaining ring (6) is embedded on the inner wall of the connecting sleeve (2) near one end of the inner drill bit (9), a through hole (11) is axially opened in the middle of the hole elastic retaining ring (6), and a protrusion (10) is extended from the spring seat (12) toward the inner drill bit (9), and the protrusion (10) is arranged through the through hole (11).
3. The safer medical craniotomy self-stop drill according to claim 1 or 2, characterized in that: A plurality of tapered holes (14) are evenly distributed on the circumferential wall of the connecting sleeve (2), and steel balls (4) are installed in the tapered holes (14).
4. The safer medical craniotomy self-stopping drill according to claim 3 is characterized in that: A first arc groove (15) is formed on the outer circumferential wall of the locking ejector pin (1), and a second arc groove (13) is formed on the inner circumferential wall of the housing (5). Both the first arc groove (15) and the second arc groove (13) are matched with the protruding surface of the steel ball (4).
5. The safer medical craniotomy self-stopping drill according to claim 4 is characterized in that: The number of the tapered holes (14) is at least three.
6. The safer medical craniotomy self-stopping drill according to claim 5, characterized in that: The outer drill bit (8) is connected to the inner drill bit (9) via a cylindrical pin (7).