CN114587509B

CN114587509B - Wireless ultrasonic knife

Info

Publication number: CN114587509B
Application number: CN202210234037.5A
Authority: CN
Inventors: 洪文亮; 张学武
Original assignee: Suzhou Ruinuo Medical Technology Co ltd
Current assignee: Suzhou Ruinuo Medical Technology Co ltd
Priority date: 2022-03-09
Filing date: 2022-03-09
Publication date: 2024-04-05
Anticipated expiration: 2042-03-09
Also published as: CN114587509A

Abstract

The invention discloses a cordless ultrasonic knife, which comprises a knife head assembly, a half-wavelength transducer, a handle shell, a circuit board and a battery, wherein a knife head of the knife head assembly is an elbow and is of a variable cross-section structure; the length of the concave arc cutting surface on the side surface of the cutter head is longer than that of the concave arc cutting surface on the main shaft surface; the front end of the half-wavelength transducer is in threaded connection with the tool bit assembly, the rear end of the half-wavelength transducer is installed in the handle shell, the half-wavelength transducer is in rolling contact with the handle shell, the circuit board and the battery are fixed in the handle shell, the battery is electrically connected with the circuit board, the positive electrode conducting ring and the negative electrode conducting ring are coaxially sleeved on the half-wavelength transducer, and the positive electrode conducting ring and the negative electrode conducting ring are respectively in elastic electrical contact with the circuit board. The cutter head has uniform amplitude distribution and good cutting and hemostasis effects; the resistance generated when the cutter head component rotates is reduced, so that the efficiency is improved; the positive electrode conductive ring and the negative electrode conductive ring are in elastic contact with the circuit board, contact is kept all the time, working stability is guaranteed, and working efficiency is improved.

Description

Wireless ultrasonic knife

Technical Field

The invention relates to the technical field of medical appliances, in particular to a cordless ultrasonic knife.

Background

The principle of the ultrasonic knife is that an ultrasonic transducer is utilized to generate vibration, the generated ultrasonic wave propagates along the longitudinal axis of the knife bar, then vibration with amplified amplitude is generated on the knife bar along the axis, finally high-speed longitudinal mechanical movement is generated at the end part of the knife head, the mechanical vibration at the end part of the knife head is very effective when cutting soft tissues, and the heat generated by the ultrasonic high-frequency vibration can coagulate the tissues and close blood vessels. Such instruments are particularly useful in minimally invasive procedures, such as endoscopic or laparoscopic procedures, because the knife bar may be easily accessed through the cannula. The key to ultrasonic blade control is to control the amplitude of vibration of the blade while producing resonance along the length of the blade bar to achieve optimal performance during the surgical procedure. However, generating an effective drive signal is challenging, such as the frequency, current and voltage applied to the transducer must all be dynamically controlled, as these parameters change with changing loads on the tool bit and temperature differences created by the tool holder. These factors result in the control system of the ultrasonic blade being a relatively complex analog-to-digital hybrid circuit with a processor and having real-time control software and man-machine interaction software running on the processor. Because of the high requirements on the control system, most ultrasonic knife products in the current market are corded products, and the ultrasonic knife needs to be connected to a desk generator when in use. The disadvantage of this design in application is that the connecting wires lead to a involvement in the operation and are inconvenient to use. The existing corded transducer has the length of 92.8mm, the weight of 40.96g, long length, heavy weight and heavy use.

Therefore, the cordless ultrasonic knife is generated, the whole ultrasonic knife can work independently without connecting a desk generator, and doctors are not bothered by the following wires in use. Cordless ultrasonic blades are favored for their convenience and efficiency. Because of portability, weight, volume and working efficiency become important indicators of cordless ultrasonic blades.

Cordless ultrasonic blades are comprised primarily of a transducer, a blade assembly, a handle housing, a circuit board, and a battery, which also determine the weight, bulk, and efficiency of the cordless ultrasonic blade. However, the existing cordless ultrasonic knife is unstable in contact with all parts, so that the working efficiency of the cordless ultrasonic knife is affected. Moreover, the cutter head component is the most critical component for determining the working efficiency of the ultrasonic cutter, the cutter head is an elbow at present, but the thickness from the cutter tail to the cutter tip is the same or gradually decreases, so that the amplitude distribution is uneven, and the cutting and hemostasis effects are required to be improved.

Disclosure of Invention

In order to solve the problems that the contact of all parts of the existing cordless ultrasonic knife is unstable, the amplitude distribution is uneven due to the shape of the cutter head, the working efficiency is affected, and the like, the invention innovatively provides the cordless ultrasonic knife, wherein the cutter head of the cordless ultrasonic knife adopts a variable cross-section design, the length of a side cutting surface is larger than that of a main shaft cutting surface, the amplitude distribution of the cutter head is even, and the cutting and hemostasis effects are good; the half-wavelength transducer and the handle shell always keep rolling contact, so that resistance generated when the cutter head assembly rotates is reduced, the resistance is minimized when the cutter head assembly rotates, and the efficiency is improved; the positive electrode conductive ring and the negative electrode conductive ring are in elastic contact with the circuit board, contact is kept all the time, working stability is guaranteed, and working efficiency is improved.

In order to achieve the technical purpose, the invention discloses a cordless ultrasonic knife, which comprises a knife head assembly, a half-wavelength transducer, a handle shell, a circuit board and a battery, wherein the knife head assembly comprises a conducting rod and a knife head, the conducting rod is connected with a knife tail of the knife head, the knife head is an elbow, the knife head comprises a first cutting section, a second cutting section, a third cutting section and a fourth cutting section which are sequentially arranged from the knife head to the knife tail, the thickness of the knife head is d1, the thickness of the boundary between the first cutting section and the second cutting section is d2, the thickness of the boundary between the second cutting section and the third cutting section is d3, the thickness of the boundary between the third cutting section and the fourth cutting section is d4, d1 is less than d2, d2 is greater than d3 is less than d4, the thickness of the first cutting section gradually increases from d1 to d2 along the direction from the knife head to the knife tail, the thickness of the second cutting section gradually increases from d2 along the direction from d3 to the third cutting section to d3 along the direction from d 3; the main shaft surface and at least one side surface of the cutter head are provided with concave arc cutting surfaces, and the length of the concave arc cutting surfaces on the side surfaces is longer than that of the concave arc cutting surfaces on the main shaft surface;

the front end of the half-wavelength transducer is in threaded connection with the tool bit assembly, the rear end of the half-wavelength transducer is installed in the handle shell, the half-wavelength transducer is in rolling contact with the handle shell, the circuit board and the battery are fixed in the handle shell, the battery is electrically connected with the circuit board, an anode conducting ring and a cathode conducting ring are coaxially sleeved on the half-wavelength transducer, and the anode conducting ring and the cathode conducting ring are respectively in elastic electrical contact with the circuit board.

Further, the outer peripheral surfaces of the positive electrode conducting ring and the negative electrode conducting ring are arc-shaped surfaces, contact spherical surfaces corresponding to the positions of the positive electrode conducting ring and the conducting ring are arranged on the circuit board, and the two contact spherical surfaces of the circuit board are respectively in elastic contact with the outer peripheral surfaces of the positive electrode conducting ring and the negative electrode conducting ring.

Further, two contact spherical surfaces on the circuit board are elastic surfaces, and the rigidity of the contact spherical surfaces is smaller than that of the positive electrode conductive ring and the negative electrode conductive ring.

Further, the half wavelength transducer includes preceding metal piece, piezoelectricity crystal heap, back metal piece and pretension screw, preceding metal piece is multistage variable order structure or echelonment structure, the inside screw hole that is equipped with along the axis of preceding metal piece, back metal piece piezoelectricity crystal heap with preceding metal piece is in with the coaxial sleeve in proper order on pretension screw's the nail pole, pretension screw's nail pole with preceding metal piece's screw hole threaded connection, back metal piece piezoelectricity crystal heap is compressed tightly pretension screw's pin head with preceding metal piece between, preceding metal piece with piezoelectricity crystal heap contact's tip is flange portion, be equipped with the screw thread on the straight section outer peripheral face of preceding metal piece's the foremost.

Further, the outer part of the flange part is wrapped with a fixing piece, the outer peripheral surface of the fixing piece is an arc-shaped surface, and the outer peripheral surface of the fixing piece is in rolling contact with the handle shell.

Further, vibration isolating rings are filled between the fixing piece and the flange part, the fixing piece comprises a front fixing ring and a rear fixing ring, and the front fixing ring is in interference fit connection with the rear fixing ring.

Further, the front metal block comprises a flange part, a first transition section, a first straight section, a second transition section and a second straight section which are sequentially connected along the direction far away from the piezoelectric crystal stack, the outer diameter of the first transition section and the outer diameter of the second transition section are gradually reduced along the direction far away from the piezoelectric crystal stack, the outer diameter of the flange part is larger than the maximum outer diameter of the first transition section, the outer diameter of the first straight section is identical to the minimum outer diameter of the first transition section, the maximum outer diameter of the second transition section is equal to or smaller than the outer diameter of the first straight section, the outer diameter of the second straight section is identical to the minimum outer diameter of the second transition section, and the threads are arranged on the outer peripheral surface of the second straight section.

Further, the outer peripheral surfaces of the first transition section and the second transition section are arc-shaped surfaces, and the radian of the arc-shaped surface of the first transition section is matched with the radian of the thumb of a human body.

Further, the front metal block comprises a flange part, a first transition section, a first straight section, a second transition section, a second straight section, a third transition section, a third straight section, a fourth transition section and a fourth straight section which are sequentially connected along the direction far away from the piezoelectric crystal stack, wherein the outer diameter of the flange part is larger than the maximum outer diameter of the first transition section, the outer diameter of the first transition section and the outer diameter of the second transition section are gradually reduced along the direction far away from the piezoelectric crystal stack, the outer diameter of the third transition section and the outer diameter of the fourth transition section are gradually increased along the direction far away from the piezoelectric crystal stack, the outer diameter of the first straight section is identical to the minimum outer diameter of the first transition section, the outer diameter of the second straight section, the minimum outer diameter of the second transition section and the minimum outer diameter of the third transition section are identical, the outer diameter of the third straight section is identical to the minimum outer diameter of the fourth transition section, the outer diameter of the fourth straight section is gradually reduced along the direction far away from the piezoelectric crystal stack, and the outer diameter of the fourth straight section is smaller than the outer diameter of the fourth straight section.

Further, the outer peripheral surfaces of the first transition section and the second transition section are arc-shaped surfaces, the radian of the arc-shaped surfaces of the first transition section is matched with the radian of the thumb of a human body, and the outer peripheral surfaces of the third transition section and the fourth transition section are conical surfaces.

The beneficial effects of the invention are as follows:

the tool bit of the cordless ultrasonic knife adopts a variable cross-section design, and the length of the side cutting surface is longer than that of the main shaft cutting surface, so that the amplitude distribution is uniform, and the cutting and hemostasis effects are good; the half-wavelength transducer and the handle shell always keep rolling contact, so that resistance generated when the cutter head assembly rotates is reduced, the resistance is minimized when the cutter head assembly rotates, and the efficiency is improved; the positive electrode conductive ring and the negative electrode conductive ring are in elastic contact with the circuit board, contact is kept all the time, working stability is guaranteed, and working efficiency is improved.

Drawings

FIG. 1 is a schematic structural view of a cordless ultrasonic knife according to an embodiment of the present invention;

FIG. 2 is a side view of a cutter head assembly of an embodiment of the present invention;

FIG. 3 is a front view of a cutter head assembly of an embodiment of the present invention;

FIG. 4 is a graph comparing the uniformity of the cutting surface amplitude of a cutting head according to an embodiment of the present invention with a constant thickness cutting head;

FIG. 5 is a schematic diagram of the connection relationship of a half-wavelength transducer, positive and negative conductive rings and a fixture according to an embodiment of the present invention;

FIG. 6 is a schematic illustration of the contact between the positive and negative conductive rings and the circuit board according to an embodiment of the present invention;

FIG. 7 is a side view of a front retaining ring of an embodiment of the present invention;

FIG. 8 is an inner end face view of a front retaining ring of an embodiment of the present invention;

FIG. 9 is a side view of a rear retaining ring of an embodiment of the present invention;

FIG. 10 is an inner end face view of a rear retaining ring of an embodiment of the present invention;

FIG. 11 is a schematic view of the contact of the securing member with the handle housing in accordance with an embodiment of the present invention;

FIG. 12 is a schematic diagram of a half-wavelength transducer according to an embodiment of the present invention;

fig. 13 is a schematic structural view of a half-wavelength transducer according to another embodiment of the present invention.

In the drawing the view of the figure,

1. a cutter head assembly; 11. a cutter head; 12. a conductive rod; 2. a half wavelength transducer; 21. a front metal block; 211. a flange portion; 212. a first transition section; 213. a first straight section; 214. a second transition section; 215. a second straight section; 216. a third transition section; 217. a third straight section; 218. a fourth transition section; 219. a fourth straight section; 22. a piezoelectric crystal stack; 23. a rear metal block; 24. pre-tightening a screw; 25. a fixing member; 251. a front fixing ring; 252. a rear fixing ring; 26. vibration isolator; 3. a handle housing; 4. a circuit board; 41. a contact sphere; 5. a battery; 6. a positive electrode conductive ring; 7. a negative electrode conductive ring.

Detailed Description

The cordless ultrasonic knife provided by the invention is explained and illustrated in detail below with reference to the accompanying drawings.

The embodiment specifically discloses a cordless ultrasonic knife, as shown in fig. 1, including tool bit assembly 1, half wavelength transducer 2, handle shell 3, circuit board 4 and battery 5, the front end and the tool bit assembly 1 threaded connection of half wavelength transducer 2 for tool bit assembly 1 can 360 rotation, and then makes tool bit assembly 1 can rotate for the handle shell axial. The rear end of the half-wavelength transducer 2 is arranged in the handle shell 3, the half-wavelength transducer 2 is in rolling contact with the handle shell 3, the circuit board 4 and the battery 5 are fixed in the handle shell 3, and the battery 5 is electrically connected with the circuit board 4. As shown in fig. 1, the half-wavelength transducer 2 is coaxially sleeved with a positive conductive ring 6 and a negative conductive ring 7, the centers of the positive conductive ring 6 and the negative conductive ring 7 coincide with the axis of the half-wavelength transducer 2, the positive conductive ring 6 and the negative conductive ring 7 are respectively in elastic electrical contact with the circuit board 4, the positive conductive ring 6 and the negative conductive ring 7 receive an electrical signal input by the circuit board 4, and then the electrical signal is transmitted to the half-wavelength transducer 2, so that the transducer is driven to generate ultrasonic mechanical energy. A certain distance is kept between the positive electrode conductive ring 6 and the negative electrode conductive ring 7 so as not to be short-circuited. The half-wavelength transducer 2 and the handle shell 3 always keep rolling contact, so that resistance generated when the cutter head assembly 1 rotates is reduced, the resistance during rotation is minimized, and the efficiency is improved. The positive electrode conductive ring 7 is in elastic contact with the circuit board 4, so that the contact is kept all the time, the working stability is ensured, and the working efficiency is improved.

As shown in fig. 2, the cutter head assembly 1 comprises a conductive rod 12 and a cutter head 11, the conductive rod is connected with the cutter tail of the cutter head, the cutter head 11 is an elbow, the cutter head 11 comprises a first cutting section, a second cutting section, a third cutting section and a fourth cutting section which are sequentially arranged from the cutter head to the cutter tail, the thickness of the cutter head is d1, the thickness of the boundary between the first cutting section and the second cutting section is d2, the thickness of the boundary between the second cutting section and the third cutting section is d3, the thickness of the boundary between the third cutting section and the fourth cutting section is d4, d1 is less than d2, d2 is greater than d3, d3 is less than d4, d2 and d4 are all smaller than the thickness of the conductive rod, the conductive rod is in a cylinder shape with a flange on an axis, the thickness of the conductive rod is equal to the diameter outside the flange part, the thickness of the first cutting section gradually increases from d1 to d2 along the direction from the cutter head to the cutter tail, the thickness of the second cutting section gradually decreases from d2 to d3 along the direction from the cutter head to the cutter tail, and the thickness of the third cutting section gradually increases from d3 along the thickness of the third cutting section gradually increases from d3 to d4 along the thickness along the direction from d3 to d4. In this embodiment, d1 < d3, d2 < d4. The pressure of the cutter point is minimum, so that the thickness d1 of the cutter point is minimum, the uniformity of the pressure is effectively balanced, and the cutter point is thinned; gradually thickening from the cutter point to the cutter tail, wherein the amplitude at the boundary of the first cutting section and the second cutting section is maximum, and d2 is the position with the maximum thickness in the first cutting section and the second cutting section in order to balance the amplitude; the thickness is reduced to d3 again after the maximum amplitude position is passed, the boundary position of the second cutting section and the third cutting section is the maximum stress position, the thickness of the boundary position is d3, and in order to prevent the cutter head from breaking, the thickness is gradually increased to d4, the design can greatly improve the working efficiency and quality of the ultrasonic knife operation, the cutting is faster, and the hemostatic effect is better.

The hemostatic effect of the ultrasonic knife and the elbow shape of the knife head are important. Theory and experiment show that the more uniform the distribution of acoustic parameters (amplitude) in the elbow operation area is, the better the cutting and hemostasis effects are. The ultrasonic knife cuts hemostasis and the amplitude A and the pressure T of the elbow are respectively in a proportional relation, namely: p=k1×ak2×t, and the more uniform the amplitude a and pressure T, the more excellent the hemostasis is cut, while K1 > K2, where P represents the cutting power of the cutter head, K1 represents the influence factor of the amplitude, and K2 represents the influence factor of the pressure.

With the flange surface (i.e., the tip) at the most distal node of the conductive rod 12 as the supporting point, the distal end of the present embodiment refers to the tip direction, the proximal end refers to the tip tail direction, and according to the moment principle, the smaller the force F generated by the more distal end, the smaller the area of the corresponding contact surface can be reduced according to t=f/S in order to balance the pressure, so that the thickness d1 of the most distal end (i.e., the tip) of the cutter head is thinnest, and gradually increases along the proximal end (the thickness of the first cutting segment gradually increases), and changes to the point of maximum amplitude (the boundary between the first cutting segment and the second cutting segment), and gradually decreases along the proximal end (the thickness of the second cutting segment gradually decreases), because the influence of the amplitude a is greater than that of the pressure T, and thus the amplitude distribution is set more uniformly. Also, since the stress is greatest toward the step near the proximal end node of the cutter head, the thickness near the node step will increase (the thickness of the third cutting segment gradually increases) in order to reduce the working stress and prevent the cutter from breaking. According to the relation between the amplitude and the stress and the hemostatic effect, the thickness change of the cutter head is set, so that the amplitude distribution is more uniform, and the cutting and hemostatic effects are better.

As shown in fig. 3, the spindle surface and at least one side surface of the cutter head are provided with concave arc cutting surfaces, and the length L1 of the concave arc cutting surfaces on the side surfaces is greater than the length L2 of the concave arc cutting surfaces on the spindle surface, so that the vibration characteristics of the cutter head are further balanced. In this embodiment, the spindle surface refers to the concave surface of the tool bit. The concave arc cutting surface on the side surface and the concave arc cutting surface on the main shaft surface are respectively started from the cutter point, the concave arc cutting surfaces on the side surface are distributed on the first cutting section, the second cutting section, the third cutting section and part of the fourth cutting section, and the concave arc cutting surfaces on the main shaft surface are distributed on the first cutting section, the second cutting section, the third cutting section and part of the fourth cutting section. The length L1 of the concave arc cutting surface on the side surface is 16-19 mm, and the length L2 of the concave arc cutting surface on the main shaft surface is 12-15.8 mm.

In this embodiment, the thickness d1 of the tip is 1.1mm, the thickness d2 at the boundary between the first cutting segment and the second cutting segment is 1.32mm, the thickness d3 at the boundary between the third cutting segment and the fourth cutting segment is 1.25mm, d4 is 1.47mm, and the thickness of the conventional equal-thickness blade is 1.47mm. The corresponding length of each section is as follows: the length of the first cutting section is 4.8mm, the length of the second cutting section is 2.8mm, the length of the third cutting section is 3.5mm, the total length of the cutter head assembly is 403mm, and the lengths of the fourth cutting section and the conducting rod can be set according to actual needs. The length L1 of the concave arc cutting surface on the side surface is 19mm, and the length L2 of the concave arc cutting surface on the main shaft surface is 15.6mm. Fig. 4 is a graph showing the amplitude uniformity of the cutting surface of the tool bit according to the present embodiment compared with that of the conventional constant thickness tool bit. The uniformity of the amplitude of the edge cutting surface of the uniform-thickness cutter head was about 66%, while the amplitude of the edge cutting surface of the cutter head of the present embodiment was about 77%, and the uniformity of the amplitude was higher by 11%.

Through detection, the amplitude distribution uniformity of the operation area of the cutter head of the embodiment is higher than that of a traditional elbow with a uniform section by more than 10%, the operation speed and accuracy are greatly improved, and a better cutting hemostasis effect is achieved.

In this embodiment, as shown in fig. 5 and 6, the outer peripheral surfaces of the positive electrode conductive ring 6 and the negative electrode conductive ring 7 are arc surfaces, the arc surfaces of the positive electrode conductive ring 6 and the negative electrode conductive ring 7 are convex outwards, and the circuit board 4 is provided with contact spherical surfaces 41 corresponding to the positions of the positive electrode conductive ring 6 and the conductive ring, and as shown in fig. 6, the two contact spherical surfaces 41 of the circuit board 4 are respectively in elastic contact with the outer peripheral surfaces of the positive electrode conductive ring 6 and the negative electrode conductive ring 7. The surface of the contact sphere 41 is plated with gold, so that the transmission performance of the electric signal is ensured. The two contact spherical surfaces 41 on the circuit board 4 are elastic surfaces, and the rigidity of the contact spherical surfaces 41 is smaller than the rigidity of the positive electrode conductive ring 6 and the negative electrode conductive ring 7. After the half-wavelength transducer 2, the positive electrode conducting ring 6 and the negative electrode conducting ring 7 are installed in the handle shell 3, the two contact spherical surfaces 41 of the circuit board 4 are extruded by the positive electrode conducting ring 6 and the negative electrode conducting ring 7 to generate micro deformation, the positive electrode conducting ring 6 and the negative electrode conducting ring 7 cannot deform and bend, and the contact spherical surfaces 41 of the circuit board 4 apply elastic force to the positive electrode conducting ring 6 and the negative electrode conducting ring 7, so that the positive electrode conducting ring 6 and the negative electrode conducting ring 7 are respectively in close contact with the circuit board 4, the contact stability is ensured, and the electric signals are stably transmitted.

As shown in fig. 5, the half-wavelength transducer 2 includes a front metal block 21, a piezoelectric crystal stack 22, a rear metal block 23, and a pre-tightening screw 24, where in this embodiment, the front metal block 21 and the rear metal block 23 are both aluminum alloy blocks, and the pre-tightening screw 24 is a titanium alloy screw, so that the weight of the transducer can be reduced while the mechanical properties are ensured. The piezo stack 22, the rear metal block 23 and the pretensioning screw 24 are located in the handle housing. The front metal block 21 is of a multi-stage variable-order structure or a step-like structure, the front metal block 21 of the multi-stage variable-order structure or the step-like structure reduces the weight of the transducer, reduces the volume of the transducer, improves the acoustic performance, obtains larger gain, and simultaneously meets the mechanical strength. The inside screw hole that is equipped with along the axis of preceding metal piece 21, back metal piece 23, piezoelectricity crystal heap 22 and preceding metal piece 21 coaxial sleeve in proper order is established on the nail pole of pretension screw 24, the nail pole of pretension screw 24 and the screw hole threaded connection of preceding metal piece 21, back metal piece 23, piezoelectricity crystal heap 22 are compressed tightly between the pin head of pretension screw 24 and preceding metal piece 21, the tip that preceding metal piece 21 contacted with piezoelectricity crystal heap 22 is flange portion 211, the flange face of flange portion 211 better gives piezoelectricity crystal heap 22 with pressure evenly. The straight section outer peripheral surface of the forefront end of the front metal block 21 is provided with threads, and the threads of the forefront end of the front metal block 21 are directly connected with the threads of the tool bit assembly 1, so that the assembly is simple. The outer diameter of the nail head of the pre-tightening screw 24 is larger than the outer diameter of the nail rod, the front end face of the nail head is attached to the rear end face of the rear metal block 23, the front end face of the rear metal block 23 is attached to the rear end face of the piezoelectric crystal stack 22, and the front end face of the piezoelectric crystal stack 22 is attached to the rear end face of the front metal block 21, namely, the flange face of the flange part of the front metal block 21. The head of the pre-tightening screw 24 and the front metal block 21 generate uniform clamping force, and the pressure is uniformly transmitted to the rear metal block 23 and the piezoelectric crystal stack 22, so that the piezoelectric crystal stack 22 can obtain uniform pressure distribution, the electromechanical conversion efficiency of the transducer is effectively improved, and the low-impedance and high-output performance of the transducer is realized.

The flange 211 is wrapped with a fixing member 25, the outer circumferential surface of the fixing member 25 is an arc surface, and the outer circumferential surface of the fixing member 25 is in rolling contact with the handle housing 3. The flange 211 is wrapped inside by the fixing piece 25, the whole outer peripheral surface of the fixing piece 25 is in an arc cylindrical shape, and the center of the arc faces the axis of the flange 211, namely, the arc surface of the fixing piece 25 protrudes outwards.

In this embodiment, as shown in fig. 5, vibration isolation rings 26 are filled between the fixing member 25 and the flange portion 211, the front end and the rear end of the flange portion 211 are both provided with one vibration isolation ring 26, the area of the vibration isolation ring 26 is larger than or equal to the end surface area of the flange portion 211, and the vibration isolation ring 26 is made of elastic material, preferably silicone rubber. The fixing member 25 comprises a front fixing ring 251 and a rear fixing ring 252, the front fixing ring 251 is fixed in front of the vibration isolator 26 at the front side of the flange 211, the rear fixing ring 252 is fixed behind the vibration isolator 26 at the rear side of the flange 211, as shown in fig. 7-10, the front fixing ring 251 and the rear fixing ring 252 are in cap shapes, the rear fixing ring 252 is buckled in the front fixing ring 251, the outer peripheral surface of the front fixing ring 251 is an arc surface protruding outwards, the front fixing ring 251 and the rear fixing ring 252 are in interference fit connection, and the front fixing ring 251 and the rear fixing ring 252 are firmly wrapped outside the flange 211, so that separation caused by vibration during operation of the ultrasonic knife is avoided. In other embodiments, the front fixing ring may be fixed in the rear fixing ring, where the outer peripheral surface of the rear fixing ring is an arc surface.

To further satisfy the weight minimization, the front fixing ring 251 and the rear fixing ring 252 are made of nonmetal high temperature resistant materials, such as PEEK (polyetheretherketone), PPSU (polyphenylene sulfone resin), etc.

As shown in fig. 7 and 8, the inner end surface of the front fixing ring 251 is provided with annular protrusions, and as shown in fig. 9 and 10, the inner end surface of the rear fixing ring 252 is provided with a plurality of protrusions uniformly distributed in the circumferential direction, and the annular protrusions and the protrusions are pressed against the vibration isolator 26 to press the vibration isolator 26 against the flange portion 211.

As shown in fig. 11, when the half-wavelength transducer is mounted in the handle housing 3, a certain gap exists between the outer peripheral surface of the fixture and the handle housing 3, and the contact area is smaller and thus the resistance is smaller than the contact between planes.

In the present embodiment, as shown in fig. 12, the front metal block 21 includes a flange portion 211, a first transition piece 212, a first straight piece 213, a second transition piece 214, and a second straight piece 215 that are sequentially connected in a direction away from the piezoelectric crystal stack 22, the outer diameter of the first transition piece 212 and the outer diameter of the second transition piece 214 gradually decrease in the direction away from the piezoelectric crystal stack 22, the outer diameter of the flange portion 211 is larger than the maximum outer diameter of the first transition piece 212, the outer diameter of the first straight piece 213 is the same as the minimum outer diameter of the first transition piece 212, the maximum outer diameter of the second transition piece 214 is equal to or smaller than the outer diameter of the first straight piece 213, the outer diameter of the second straight piece 215 is the same as the minimum outer diameter of the second transition piece 214, and threads are provided on the outer circumferential surface of the second straight piece 215. The outer peripheral surfaces of the flange 211, the first straight section 213 and the second straight section 215 are all straight cylindrical surfaces, and the first transition section 212 and the second transition section 214 realize smooth transition, so that the diameter of the front metal block 21 is reduced gradually for the second time, the volume and the weight are reduced, the mechanical strength of the front metal block 21 is ensured, and the vibration amplitude when the piezoelectric crystal stack 22 is subjected to the vibration transmitted is larger.

The outer peripheral surfaces of the first transition section 212 and the second transition section 214 are arc-shaped surfaces, and the radian of the arc-shaped surfaces of the first transition section 212 is matched with the radian of the thumb of a human body. When the half-wavelength transducer 2 is connected with the tool bit assembly 1, the flange 211 of the transducer is held by a hand, the thumb is held on the arc surface of the first transition section 212, the torque wrench is fastened from the end of the tool bit assembly 1, the arc surface of the first transition section 212 is matched with the arc surface of the thumb, and the torque wrench is supported to adapt to the thumb, so that the torque wrench is convenient to grasp and apply force well.

In this embodiment, the ratio of the outer diameter of the flange portion to the maximum outer diameter of the first transition section is 7: and 6, the outer diameter ratio of the flange part 5 to the first straight section is 2:1, the outer diameter ratio of the first straight section to the second straight section is 3:2, and the outer diameter ratio can fully ensure the mechanical strength and the acoustic performance of the transducer.

The acoustic properties of the half wavelength transducer 2 of this example were compared with those of a conventional corded transducer, as shown in table 1. The length of the existing corded ultrasonic transducer is 92.8mm, the outer diameter of the piezoelectric crystal stack, the outer diameter of the rear metal block and the outer diameter of the pre-tightening screw head of the existing corded ultrasonic transducer are identical to those of the existing corded ultrasonic transducer, the front metal block of the existing corded ultrasonic transducer is made of aluminum alloy, the rear metal block of the existing corded ultrasonic transducer is made of stainless steel, the pre-tightening screw of the existing corded ultrasonic transducer is made of titanium alloy, and the outer diameter of the front metal block of the existing corded ultrasonic transducer is identical to the maximum outer diameter of the first transition section of the existing corded ultrasonic transducer. In this embodiment, the flange portion has an outer diameter of 18mm, the first transition section has a maximum outer diameter of 15.4mm, the first straight section has an outer diameter of 9mm, and the second straight section has an outer diameter of 6mm. The length of flange portion is 2mm, and the length of first changeover portion is 2.5mm, and the length of first straight section is 10mm, and the length of second changeover portion is 2mm, and the length of second straight section is 14mm, and the length of piezoelectricity crystal stack is 10.2mm, and the length of back metal piece is 6mm, and pretension screw's pin fin length is 4.7mm.

TABLE 1

As can be seen from comparing the data in table 1, the acoustic characteristics of the transducer of this embodiment are improved, and the phase margin is nearly doubled. The increase of the phase margin of the transducer near the resonance point is more beneficial to the matching of the transducer and a host machine, and the working efficiency of the cordless ultrasonic transducer is improved.

In another embodiment, as shown in fig. 13, the front metal block 21 includes a flange portion 211, a first transition portion 212, a first straight portion 213, a second transition portion 214, a second straight portion 215, a third transition portion 216, a third straight portion 217, a fourth transition portion 218, and a fourth straight portion 219 that are sequentially connected in a direction away from the piezoelectric stack 22, the flange portion 211 having an outer diameter larger than a maximum outer diameter of the first transition portion 212, the first transition portion 212 having an outer diameter smaller than an outer diameter of the second transition portion 214, the third transition portion 216 having an outer diameter smaller than an outer diameter of the fourth transition portion 218, the fourth transition portion 218 having an outer diameter larger than an outer diameter of the fourth transition portion 219, the first straight portion 213 having an outer diameter equal to a minimum outer diameter of the first transition portion 212, the second straight portion 215 having an outer diameter equal to a minimum outer diameter of the second transition portion 214, the third straight portion 218 having an outer diameter equal to a minimum outer diameter of the fourth transition portion 219, and the fourth straight portion 219 having an outer diameter equal to an outer diameter of the fourth straight portion 219 disposed on an outer diameter of the fourth straight portion 219. The outer circumferential surfaces of the first straight section 213, the second straight section 215, the third straight section 217 and the fourth straight section 219 are straight cylindrical surfaces, the first transition section 212, the second transition section 214, the third transition section 216 and the fourth transition section 218 realize smooth transition, the outer diameters of the first transition section 212 and the second transition section 214 are gradually reduced, the vibration amplitude is gradually increased while the volume and the weight are reduced, the outer diameters of the third transition section 216 and the fourth transition section 218 are gradually increased, but the increasing proportion is smaller, the outer diameter of the front metal block 21 is integrally reduced from the rear to the front, the acoustic performance is improved, larger gain is obtained, and meanwhile the mechanical strength is met. Preferably, the maximum outer diameter of the third transition section 216 is less than the maximum outer diameter of the second transition section 214. The front metal block 21 with the variable-order structure reduces the diameter for a plurality of times, ensures the mechanical strength of the front metal block 21, and simultaneously has larger vibration amplitude when being subjected to the vibration transmitted by the piezoelectric crystal stack 22.

The first and second straight sections are of greater significance for the resonant frequency and amplitude gain of the transducer, and therefore the first and second straight sections are of greater length and diameter than the third and fourth straight sections, with the ratio of diameters of the first and second straight sections approximately: phi 1/phi 2 is approximately equal to 2. In order to maintain mechanical properties, the ratio of the sum of the lengths of the first transition section, the first straight section, the second transition section and the second straight section to the overall length of the front metal block is greater than 1/2, more preferably greater than 0.7.

The outer peripheral surfaces of the first transition section 212 and the second transition section 214 are arc surfaces, the radian of the arc surfaces of the first transition section 212 is matched with the radian of the thumb of a human body, and the outer peripheral surfaces of the third transition section 216 and the fourth transition section 218 are conical surfaces. When the half-wavelength transducer 2 is connected with the tool bit assembly 1, the flange 211 of the transducer is held by a hand, the thumb is held on the arc surface of the first transition section 212, the torque wrench is fastened from the end of the tool bit assembly 1, the arc surface of the first transition section 212 is matched with the arc surface of the thumb, and the torque wrench is supported to adapt to the thumb, so that the torque wrench is convenient to grasp and apply force well. The third transition section 216 and the fourth transition section 218 are tapered surfaces to increase mechanical strength.

The acoustic properties of the conventional corded transducer and the wireless transducer of this example were compared as shown in table 2. The length of the existing corded ultrasonic transducer is 92.8mm, the outer diameter of the rear metal block, the outer diameter of the piezoelectric crystal stack and the outer diameter of the pre-tightening screw head of the existing corded ultrasonic transducer are identical to those of the existing corded ultrasonic transducer, the front metal block of the existing corded ultrasonic transducer is made of aluminum alloy, the rear metal block of the existing corded ultrasonic transducer is made of stainless steel, the pre-tightening screw of the existing corded ultrasonic transducer is made of titanium alloy, and the outer diameter of the front metal block of the existing corded ultrasonic transducer is identical to the maximum outer diameter of the first transition section of the existing corded ultrasonic transducer. In this embodiment, the flange portion has a length of 2.7mm, the first transition section has a length of 4mm, the first straight section has a length of 7mm, the second transition section has a length of 1mm, the second straight section has a length of 9.5mm, the third transition section has a length of 1.2mm, the third straight section has a length of 1m, the fourth transition section has a length of 0.4mm, the fourth straight section has a length of 5mm, and the diameter ratio of the first straight section to the second straight section is 2. In this embodiment, the maximum diameter of the flange portion is 15mm, the maximum outer diameter of the first transition section is 14mm, the diameter of the first straight section is 8mm, the diameter of the second straight section is 4mm, the diameter of the third straight section is 2mm, the outer surface of the fourth straight section is threaded, and the standard of the threads is generally 4-40UNC. The length of the piezoelectric crystal stack is 7mm, the length of the rear metal block is 5mm, and the length of the nail head of the pre-tightening screw is 4mm.

TABLE 2

As can be seen from comparing the data in table 2, the acoustic characteristics of the transducer of this embodiment are improved, and the phase margin is increased by almost 47%. By the structural improvement of the front metal block 21, the acoustic characteristics are improved while the mechanical strength is ensured.

The end surface edge of the rear metal block 23, which is in contact with the nail head of the pre-tightening screw 24, is provided with a chamfer or a chamfer, so that the diameter of the peripheral surface of the rear metal block 23 is moderately increased to form a circular ring surface with a transition step, and the rear metal block 23 can better receive the pre-tightening force of the nail head of the pre-tightening screw 24 and further improve the resonance characteristic of the ultrasonic transducer. The front end surface of the rear metal block 23, i.e. the contact surface with the piezoelectric crystal stack 22, is a flat torus.

The design mode of the half-wavelength transducer 2 further reduces the size space and the weight of the ultrasonic knife and improves the comfort of use.

In conclusion, the cordless ultrasonic knife is improved in size and weight, more portable, simpler to assemble, better in cutting and hemostasis effects and effectively improves working efficiency through the structural improvement of the knife head, the electric contact improvement of the positive and negative conductive rings and the conductive plates, the structural improvement of the energy converter and the connection mode of the energy converter and the handle shell.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the description of the present specification, a description referring to the terms "present embodiment," "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any at least one embodiment or example. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

The above description is only of the preferred embodiments of the present invention, and is not intended to limit the invention, but any modifications, equivalents, and simple improvements made within the spirit of the present invention should be included in the scope of the present invention.

Claims

1. A cordless ultrasonic knife is characterized by comprising a knife head assembly (1), a half-wavelength transducer (2), a handle shell (3), a circuit board (4) and a battery (5),

the cutter head assembly (1) comprises a conducting rod (12) and a cutter head (11), the conducting rod (12) is connected with the cutter tail of the cutter head (11), the cutter head (11) is an elbow, the cutter head (11) comprises a first cutting section, a second cutting section, a third cutting section and a fourth cutting section which are sequentially arranged from the cutter head to the cutter tail, the thickness of the cutter head is d1, the thickness at the boundary of the first cutting section and the second cutting section is d2, the thickness at the boundary of the second cutting section and the third cutting section is d3, the thickness at the boundary of the third cutting section and the fourth cutting section is d4, d1 is less than d2, d2 is more than d3, d3 is less than d4, d2 and d4 are all smaller than the thickness of the conducting rod (12), the thickness of the first cutting section gradually increases from d1 to d2 along the direction from the cutter head to the cutter tail, the thickness of the second cutting section gradually decreases from d2 to d3 along the direction from d3 to d3 along the thickness of the cutter head to d4 along the direction from d4; the main shaft surface and at least one side surface of the cutter head are provided with concave arc cutting surfaces, and the length of the concave arc cutting surfaces on the side surfaces is longer than that of the concave arc cutting surfaces on the main shaft surface;

the front end of the half-wavelength transducer (2) is in threaded connection with the tool bit assembly (1), the rear end of the half-wavelength transducer (2) is installed in the handle shell (3), the half-wavelength transducer (2) is in rolling contact with the handle shell (3), the circuit board (4) and the battery (5) are fixed in the handle shell (3), the battery (5) is electrically connected with the circuit board (4), an anode conducting ring (6) and a cathode conducting ring (7) are coaxially sleeved on the half-wavelength transducer (2), and the anode conducting ring (6) and the cathode conducting ring (7) are respectively in elastic electrical contact with the circuit board (4);

the half-wavelength transducer (2) comprises a front metal block (21), a piezoelectric crystal stack (22), a rear metal block (23) and a pre-tightening screw (24), wherein the front metal block (21) is of a multi-stage variable-order structure or a stepped structure, threaded holes are formed in the front metal block (21) along the axis, the rear metal block (23), the piezoelectric crystal stack (22) and the front metal block (21) are coaxially sleeved on the screw rod of the pre-tightening screw (24) in sequence, the screw rod of the pre-tightening screw (24) is in threaded connection with the threaded holes of the front metal block (21), the rear metal block (23) and the piezoelectric crystal stack (22) are compressed between the screw head of the pre-tightening screw (24) and the front metal block (21), the contact end part of the front metal block (21) and the piezoelectric crystal stack (22) is a flange part (211), and the outer circumferential surface of the straight section of the forefront end of the front metal block (21) is provided with threads;

when the front metal block (21) is of a stepped structure, the front metal block (21) comprises a flange part (211), a first transition section (212), a first straight section (213), a second transition section (214) and a second straight section (215) which are sequentially connected along the direction far away from the piezoelectric crystal stack (22), the outer diameter of the first transition section (212) and the outer diameter of the second transition section (214) are gradually reduced along the direction far away from the piezoelectric crystal stack (22), the outer diameter of the flange part (211) is larger than the maximum outer diameter of the first transition section (212), the outer diameter of the first straight section (213) is the same as the minimum outer diameter of the first transition section (212), the maximum outer diameter of the second transition section (214) is equal to or smaller than the outer diameter of the first straight section (213), the outer diameter of the second straight section (215) is the same as the minimum outer diameter of the second transition section (214), and the outer diameter of the outer circumference of the second straight section (215) is larger than the outer diameter of the flange 7. 6, the outer diameter ratio of the flange part to the first straight section is 2:1, and the outer diameter ratio of the first straight section to the second straight section is 3:2;

when the front metal block (21) is of a multistage variable-order structure, the front metal block (21) comprises a flange part (211), a first transition section (212), a first straight section (213), a second transition section (214), a second straight section (215), a third transition section (216), a third straight section (217), a fourth transition section (218) and a fourth straight section (219) which are sequentially connected along the direction far away from the piezoelectric crystal stack (22), the outer diameter of the flange part (211) is larger than the maximum outer diameter of the first transition section (212), the outer diameters of the first transition section (212) and the second transition section (214) are gradually reduced along the direction far away from the piezoelectric crystal stack (22), the outer diameters of the third transition section (216) and the fourth transition section (218) are gradually increased along the direction far away from the piezoelectric crystal stack (22), the outer diameters of the first straight section (213) are the same as the minimum outer diameters of the first transition section (212), the outer diameters of the first straight section (215) and the fourth transition section (218) are the same as the minimum outer diameters of the third straight section (218) and the minimum outer diameters of the fourth transition section (218) are the minimum outer diameters of the first straight section (215) and the fourth transition section (218), the external diameter of the fourth straight section (219) is smaller than that of the second straight section (215), the threads are arranged on the outer peripheral surface of the fourth straight section (219), the length and the diameter of the first straight section and the second straight section are both larger than those of the third straight section and the fourth straight section, and the diameter ratio of the first straight section to the second straight section is 2:1, wherein the ratio of the sum of the lengths of the first transition section, the first straight section, the second transition section and the second straight section to the whole length of the front metal block is more than 0.7.

2. The cordless ultrasonic knife according to claim 1, wherein the outer circumferential surfaces of the positive electrode conductive ring (6) and the negative electrode conductive ring (7) are arc surfaces, contact spherical surfaces (41) corresponding to the positions of the positive electrode conductive ring (6) and the conductive ring are arranged on the circuit board (4), and the two contact spherical surfaces (41) of the circuit board (4) are respectively in elastic contact with the outer circumferential surfaces of the positive electrode conductive ring (6) and the negative electrode conductive ring (7).

3. The cordless ultrasonic blade according to claim 2, characterized in that both contact spheres (41) on the circuit board (4) are elastic surfaces, the rigidity of the contact spheres (41) being smaller than the rigidity of the positive conductive ring (6) and the negative conductive ring (7).

4. The cordless ultrasonic knife according to claim 1, wherein the flange portion (211) is externally wrapped with a fixing member (25), an outer peripheral surface of the fixing member (25) is an arc-shaped surface, and the outer peripheral surface of the fixing member (25) is in rolling contact with the handle housing (3).

5. The cordless ultrasonic knife according to claim 4, wherein a vibration isolator (26) is filled between the fixture (25) and the flange portion (211), the fixture (25) comprising a front fixing ring (251) and a rear fixing ring (252), the front fixing ring (251) and the rear fixing ring (252) being connected by an interference fit.

6. The cordless ultrasonic knife according to claim 1, wherein when the front metal block (21) is of a stepped structure, outer peripheral surfaces of the first transition section (212) and the second transition section (214) are arc surfaces, and an arc of the arc surface of the first transition section (212) is matched with an arc of a thumb of a human body.

7. The cordless ultrasonic knife according to claim 1, wherein when the front metal block (21) is of a multi-stage variable-order structure, outer peripheral surfaces of the first transition section (212) and the second transition section (214) are arc surfaces, the arc of the arc surface of the first transition section (212) is matched with the arc of a thumb of a human body, and the outer peripheral surfaces of the third transition section (216) and the fourth transition section (218) are conical surfaces.