CN114601533A

CN114601533A - Cordless ultrasonic knife

Info

Publication number: CN114601533A
Application number: CN202210232573.1A
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: 2022-06-10

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 the front end of the half-wavelength transducer is in threaded connection with the knife head 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 and are electrically connected with each other, 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. The half-wavelength transducer and the handle shell are always in rolling contact, so that the resistance generated by the cutter head assembly during rotation is reduced, the resistance during rotation is minimized, and the efficiency is improved; the positive and negative conducting rings are in elastic contact with the circuit board and always kept in contact with the circuit board, so that the working stability is ensured, and the working efficiency is improved.

Description

Cordless ultrasonic knife

Technical Field

The invention relates to the technical field of medical instruments, 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 emitted ultrasonic wave is transmitted along the longitudinal axis of a knife rod, then vibration with amplified amplitude is generated on the knife rod along the axis, finally high-speed longitudinal mechanical motion is generated at the end part of a knife head, the mechanical vibration at the tail end of the knife head is very effective in cutting soft tissues, and heat generated by ultrasonic high-frequency vibration can coagulate the tissues and close blood vessels. The instrument is particularly suitable for minimally invasive procedures, such as endoscopic or laparoscopic procedures, since the tool shaft can easily reach the surgical site through the cannula. The key to ultrasonic blade control is to control the vibration amplitude of the blade tip 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, for example the frequency, current and voltage applied to the transducer must all be dynamically controlled, since these parameters vary with changes in the load on the tool tip and the temperature difference produced by the tool holder. These factors have led to the control system of the ultrasonic blade being a relatively complex analog-to-digital hybrid circuit with a processor on which real-time control software and human-machine interaction software are run. Due to the high demands placed on the control system, most ultrasonic blade products on the market today are corded products, such as the Harmonic series of dynasty, similar to the design disclosed in US78243, which requires the ultrasonic blade to be connected to a desktop generator when in use. The disadvantage of this design in application is that the connecting wires are involved in the operation and are inconvenient to use. The existing rope transducer has the advantages of 92.8mm in length, 40.96g in weight, long length, heavy weight and heavy weight.

Therefore, the cordless ultrasonic knife comes along, so that the whole ultrasonic knife can work independently without connecting a desk type generator, and a doctor is not disturbed by a following wire in use. Cordless ultrasonic knives are favored for their convenience and efficiency. Just because of portability, weight, volume, and efficiency become important indicators for cordless ultrasonic knives.

The cordless ultrasonic blade is mainly composed of a transducer, a cutter head assembly, a handle housing, a circuit board and a battery, and the main components also determine the weight, the volume and the efficiency of the cordless ultrasonic blade. However, the conventional cordless ultrasonic knife is heavy and complex in sound structure, and the carrying of the cordless ultrasonic knife and the operation hand feeling and the working efficiency in the operation process are influenced.

Disclosure of Invention

In order to solve the problems of heavy weight, complex sound structure, influence on working efficiency and the like of the conventional cordless ultrasonic knife, the invention innovatively provides the cordless ultrasonic knife, the half-wavelength transducer of the cordless ultrasonic knife is always in rolling contact with the handle shell, so that the resistance generated when the knife head component rotates is reduced, the resistance during rotation is minimized, and the efficiency is improved; the positive and negative conducting rings are in elastic contact with the circuit board and always kept in contact with the circuit board, so that the working stability is ensured, and the 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 front end of the half-wavelength transducer is in threaded connection with the knife head 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.

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

Furthermore, the 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 conductive ring and the negative conductive ring.

Furthermore, the half-wavelength transducer comprises a front metal block, a piezoelectric crystal stack, a rear metal block and a pre-tightening screw, wherein the front metal block is of a multi-stage variable-step structure or a step-shaped structure, a threaded hole is formed in the front metal block along the axis, the rear metal block, the piezoelectric crystal stack and the front metal block are sequentially and coaxially sleeved on a screw rod of the pre-tightening screw, the screw rod of the pre-tightening screw is in threaded connection with the threaded hole of the front metal block, the rear metal block and the piezoelectric crystal stack are tightly pressed between the screw head of the pre-tightening screw and the front metal block, the end part of the front metal block in contact with the piezoelectric crystal stack is a flange part, and threads are arranged on the outer peripheral surface of a straight section of the most front end of the front metal block.

Further, the fixing piece wraps the outer portion of the flange portion, the outer peripheral face of the fixing piece is an arc face, and the outer peripheral face of the fixing piece is in rolling contact with the handle shell.

Further, the mounting with it has the vibration isolation circle to fill between the flange portion, the mounting includes preceding solid fixed ring and the solid fixed ring of back, preceding solid fixed ring with the solid fixed ring interference fit of back is connected.

Further, the front metal block comprises a flange portion, a first transition section, a first flat section, a second transition section and a second flat section, wherein the flange portion, the first transition section, the first flat section, the second transition section and the second flat section are sequentially connected in the direction 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 in the direction away from the piezoelectric crystal stack, the outer diameter of the flange portion is larger than the maximum outer diameter of the first transition section, the outer diameter of the first flat section is the same as 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 flat section, the outer diameter of the second flat section is the same as the minimum outer diameter of the second transition section, and the thread is arranged on the outer peripheral surface of the second flat section.

Furthermore, the peripheral surfaces of the first transition section and the second transition section are arc surfaces, and the radian of the arc surface of the first transition section is matched with the radian of a 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 a 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 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 the same as 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 the same, and the outer diameter of the third straight section is the same as the minimum outer diameter of the fourth transition section, the outer diameter of the fourth straight section is the same as the maximum outer diameter of the fourth transition section, the outer diameter of the fourth straight section is smaller than that of the second straight section, and the threads are arranged on the outer peripheral surface of the fourth straight section.

Furthermore, the peripheral surfaces of the first transition section and the second transition section are arc surfaces, the radian of the arc surface of the first transition section is matched with the radian of a human thumb, and the peripheral surfaces of the third transition section and the fourth transition section are conical surfaces.

The invention has the beneficial effects that:

the half-wavelength transducer of the cordless ultrasonic knife is always in rolling contact with the handle shell, so that the resistance generated when the knife head component rotates is reduced, the resistance during rotation is minimized, and the efficiency is improved; the positive and negative conducting rings are in elastic contact with the circuit board and always kept in contact with the circuit board, so that the working stability is ensured, and the working efficiency is improved.

Drawings

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

FIG. 2 is a schematic diagram of the connection of the half-wavelength transducer, the positive and negative conductive rings and the fixing member according to the embodiment of the invention;

FIG. 3 is a schematic diagram of the contact between the conductive rings and the circuit board according to the embodiment of the present invention;

FIG. 4 is a side view of a front retaining ring of an embodiment of the present invention;

FIG. 5 is an inner end view of a front retaining ring of an embodiment of the present invention;

FIG. 6 is a side view of a rear retaining ring of an embodiment of the present invention;

FIG. 7 is an inner end view of a rear retaining ring of an embodiment of the present invention;

FIG. 8 is a schematic view of the attachment of the holder to the handle housing according to an embodiment of the present invention;

FIG. 9 is a schematic structural diagram of a half-wavelength transducer of an embodiment of the present invention;

FIG. 10 is a schematic diagram of a half-wavelength transducer in accordance with another embodiment of the invention.

In the figure, the position of the upper end of the main shaft,

1. a cutter head assembly; 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 the screw; 25. a fixing member; 251. a front retaining ring; 252. a rear fixing ring; 26. a vibration isolation ring; 3. a handle housing; 4. a circuit board; 41. contacting the spherical surface; 5. a battery; 6. a positive conducting ring; 7. and a negative conducting ring.

Detailed Description

The cordless ultrasonic blade provided by the invention is explained and explained in detail in the following with the accompanying drawings of the specification.

The embodiment specifically discloses a cordless ultrasonic scalpel, as shown in fig. 1, which comprises a scalpel head assembly 1, a half-wavelength transducer 2, a handle housing 3, a circuit board 4 and a battery 5, wherein the front end of the half-wavelength transducer 2 is in threaded connection with the scalpel head assembly 1, so that the scalpel head assembly 1 can rotate by 360 degrees, and further, the scalpel head assembly 1 can axially rotate relative to the handle housing. 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. 2, the half-wavelength transducer 2 is coaxially sleeved with an anode conductive ring 6 and a cathode conductive ring 7, the centers of circles of the anode conductive ring 6 and the cathode conductive ring 7 coincide with the axis of the half-wavelength transducer 2, the anode conductive ring 6 and the cathode conductive ring 7 are respectively in elastic electrical contact with the circuit board 4, the anode conductive ring 6 and the cathode 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. The positive conductive ring 6 and the negative conductive ring 7 are kept at a certain distance to avoid short circuit. The half-wavelength transducer 2 is always in rolling contact with the handle shell 3, so that the resistance generated when the cutter head assembly 1 rotates is reduced, the resistance during rotation is minimized, and the efficiency is improved. The positive and negative conducting rings 7 are in elastic contact with the circuit board 4 and always keep contact, so that the working stability is ensured, and the working efficiency is improved.

In this embodiment, as shown in fig. 3, the outer peripheral surfaces of the positive conductive ring 6 and the negative conductive ring 7 are arc-shaped surfaces, the arc-shaped surfaces of the positive conductive ring and the negative conductive ring are both convex outward, and the circuit board 4 is provided with contact spherical surfaces 41 corresponding to the positions of the positive conductive ring 6 and the conductive ring, as shown in fig. 3, two contact spherical surfaces 41 of the circuit board 4 are respectively in elastic contact with the outer peripheral surfaces of the positive conductive ring 6 and the negative conductive ring 7. The surface of the contact spherical surface 41 is plated with gold, so that the electric signal transmission performance 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 less than that of the positive conductive ring 6 and the negative conductive ring 7. After the half-wavelength transducer 2, the anode conducting ring 6 and the cathode conducting ring 7 are installed in the handle shell 3, the two contact spherical surfaces 41 of the circuit board 4 are slightly deformed by the extrusion of the anode conducting ring 6 and the cathode conducting ring 7, the anode conducting ring 6 and the cathode conducting ring 7 cannot be deformed and bent, the contact spherical surfaces 41 of the circuit board 4 apply elasticity to the anode conducting ring 6 and the cathode conducting ring 7, so that the anode conducting ring 6 and the cathode conducting ring 7 are respectively in close contact with the circuit board 4, the contact stability is ensured, and an electric signal is stably transmitted.

As shown in fig. 2, 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, 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 ensuring the mechanical properties. The front metal block 21 is of a multi-stage variable-step structure or a stepped structure, and the front metal block 21 of the multi-stage variable-step structure or the stepped structure reduces the weight of the transducer and the size of the transducer, improves the acoustic performance, obtains larger gain and meets the mechanical strength. The front metal block 21 is internally provided with a threaded hole along the axis, the rear metal block 23, the piezoelectric crystal pile 22 and the front metal block 21 are sequentially coaxially sleeved on a nail rod of the pre-tightening screw 24, the nail rod of the pre-tightening screw 24 is in threaded connection with the threaded hole of the front metal block 21, the rear metal block 23 and the piezoelectric crystal pile 22 are tightly pressed between the nail head of the pre-tightening screw 24 and the front metal block 21, the end part of the front metal block 21, which is in contact with the piezoelectric crystal pile 22, is a flange part 211, and the flange surface of the flange part 211 better and uniformly transmits pressure to the piezoelectric crystal pile 22. The straight section of the foremost end of the front metal block 21 is provided with a thread on the outer peripheral surface, the foremost thread of the front metal block 21 is directly connected with the thread of the cutter head component 1, and the assembly is simple. The outer diameter of the head of the pretightening screw 24 is larger than that of the nail rod, the front end face of the head of the pretightening screw 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 pile 22, and the front end face of the piezoelectric crystal pile 22 is attached to the rear end face of the front metal block 21, namely attached to the flange face of the front metal block 21. The uniform clamping force is generated by the nail head of the pretightening screw 24 and the front metal block 21, 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 of the ultrasonic transducer 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 ultrasonic transducer is realized.

The fixing part 25 is wrapped outside the flange part 211, the outer peripheral surface of the fixing part 25 is an arc-shaped surface, and the outer peripheral surface of the fixing part 25 is in rolling contact with the handle shell 3. The fixing piece 25 wraps the flange part 211 inside, the whole fixing piece is in a shape of an arc cylinder with the outer peripheral surface, and the circle center of the arc is towards the axis of the flange part 211, namely, the arc surface of the fixing piece 25 is outwards protruded.

In the present embodiment, as shown in fig. 2, the vibration isolating ring 26 is filled between the fixing member 25 and the flange portion 211, the vibration isolating ring 26 is installed at both the front end and the rear end of the flange portion 211, the area of the vibration isolating ring 26 is greater than or equal to the area of the end surface of the flange portion 211, and the vibration isolating ring 26 is made of an elastic material, preferably, silicon rubber. The fixing member 25 includes a front fixing ring 251 and a rear fixing ring 252, the front fixing ring 251 is fixed in front of the vibration isolation ring 26 on the front side of the flange portion 211, the rear fixing ring 252 is fixed behind the vibration isolation ring 26 on the rear side of the flange portion 211, as shown in fig. 4 to 7, the front fixing ring 251 and the rear fixing ring 252 are in a cap shape, 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-shaped surface, the front fixing ring 251 and the rear fixing ring 252 are connected in an interference fit manner, and the flange portion 211 is firmly wrapped outside to avoid separation caused by vibration when the ultrasonic knife works. In other embodiments, the front fixing ring may be fixed in the rear fixing ring, and at this time, the outer circumferential surface of the rear fixing ring is an arc surface.

In order to further satisfy the requirement of the lightest weight, the front fixing ring 251 and the rear fixing ring 252 are made of a non-metal high temperature resistant material, and PEEK (polyether ether ketone), PPSU (polyphenylene sulfone resin), or the like may be used.

As shown in fig. 4 and 5, the inner end surface of the front fixing ring 251 is provided with an annular protrusion, and as shown in fig. 6 and 7, 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 protrusion and the protrusions are pressed against the vibration isolating ring 26 to press the vibration isolating ring 26 against the flange portion 211.

As shown in fig. 8, when the half-wavelength transducer is mounted in the handpiece housing 3, a certain gap exists between the outer peripheral surface of the fixing member and the handpiece housing 3, and the contact area and hence the resistance are smaller with respect to the contact between the flat surface and the flat surface.

In the present embodiment, as shown in fig. 9, the front metal block 21 includes a flange portion 211, a first transition section 212, a first straight section 213, a second transition section 214, and a second straight section 215, which are connected in sequence in a direction away from the piezoelectric crystal stack 22, an outer diameter of the first transition section 212 and an outer diameter of the second transition section 214 gradually decrease in a direction away from the piezoelectric crystal stack 22, an outer diameter of the flange portion 211 is larger than a maximum outer diameter of the first transition section 212, an outer diameter of the first straight section 213 is the same as a minimum outer diameter of the first transition section 212, a maximum outer diameter of the second transition section 214 is equal to or smaller than an outer diameter of the first straight section 213, an outer diameter of the second straight section 215 is the same as a minimum outer diameter of the second transition section 214, and a thread is provided on an outer circumferential surface of the second straight section 215. The outer peripheral surfaces of the flange part 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 gradually reduced for two times, the size and the weight are reduced, the mechanical strength of the front metal block 21 is ensured, and the vibration amplitude is larger when the piezoelectric crystal pile 22 transmits the vibration.

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 surface of the first transition section 212 is matched with the radian of a human thumb. When the half-wavelength transducer 2 is connected with the tool bit assembly 1, the flange part 211 of the transducer is held by a hand, a thumb is held on the arc-shaped surface of the first transition section 212, the torque wrench is fastened from the end of the tool bit assembly 1, the radian of the arc-shaped surface of the first transition section 212 is matched with the radian of the thumb, the support is adapted to the thumb, and the good grasping and force application are facilitated.

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 ratio of the outer diameters of the flange part 5 and the first flat section is 2:1, the ratio of the outer diameters of the first flat section and the second flat section is 3:2, and the ratio of the outer diameters can fully guarantee the mechanical strength and the acoustic performance of the transducer.

The acoustic properties of the half-wavelength transducer 2 of the present embodiment were compared with those of the existing corded transducer, as shown in table 1. The length of the existing rope 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 nail head of the embodiment are the same as those of the existing rope ultrasonic transducer, the front metal block of the existing rope ultrasonic transducer is made of aluminum alloy, the rear metal block of the existing rope ultrasonic transducer is made of stainless steel, the pre-tightening screw of the existing rope ultrasonic transducer is made of titanium alloy, and the outer diameter of the front metal block of the existing rope ultrasonic transducer is the same as the maximum outer diameter of the first transition section of the embodiment. In this embodiment, the outer diameter of the flange portion is 18mm, the maximum outer diameter of the first transition section is 15.4mm, the outer diameter of the first straight section is 9mm, and the outer diameter of the second straight section is 6 mm. 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 piezocrystal heap is 10.2mm, and the length of back metal block is 6mm, and the pin fin length of pretension screw is 4.7 mm.

TABLE 1

Comparing the data in table 1, it can be seen that the acoustic characteristics of the transducer of this embodiment are improved and the phase margin is almost doubled. The increase of the phase tolerance of the transducer near the resonance point is more beneficial to matching the transducer with a host machine, and the working efficiency of the transducer is improved.

In another embodiment, as shown in fig. 10, the front metal block 21 includes a flange portion 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 connected in sequence in a direction away from the piezoelectric crystal stack 22, an outer diameter of the flange portion 211 is larger than a maximum outer diameter of the first transition section 212, an outer diameter of the first transition section 212 and an outer diameter of the second transition section 214 are gradually reduced in a direction away from the piezoelectric crystal stack 22, an outer diameter of the third transition section 216 and an outer diameter of the fourth transition section 218 are gradually increased in a direction away from the piezoelectric crystal stack 22, an outer diameter of the first straight section 213 is the same as a minimum outer diameter of the first transition section 212, an outer diameter of the second straight section 215, a minimum outer diameter of the second transition section 214 and a minimum outer diameter of the third transition section 216 are the same, an outer diameter of the third straight section 217 is the same as a minimum outer diameter of the fourth transition section 218, the fourth straight section 219 has the same outer diameter as the maximum outer diameter of the fourth transition section 218, the fourth straight section 219 has an outer diameter smaller than that of the second straight section 215, and threads are provided on the outer circumferential surface of the fourth straight section 219. The outer peripheral 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 size 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 small, the outer diameter of the front metal block 21 is gradually reduced from back to front on the whole, 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 step-variable structure enables the diameter to be reduced for multiple times, the mechanical strength of the front metal block 21 is guaranteed, and meanwhile, the vibration amplitude is larger when the front metal block is subjected to vibration transmitted by the piezoelectric crystal pile 22.

The first and second straight sections are of greater significance to the resonant frequency and amplitude gain of the transducer, and therefore the first and second straight sections are each longer in length and diameter than the third and fourth straight sections, and the ratio of the diameters of the first and second straight sections is 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-shaped surfaces, the radian of the arc-shaped surface of the first transition section 212 is matched with the radian of a human thumb, 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 part 211 of the transducer is held by a hand, a thumb is held on the arc-shaped surface of the first transition section 212, the torque wrench is fastened from the end of the tool bit assembly 1, the radian of the arc-shaped surface of the first transition section 212 is matched with the radian of the thumb, the support is adapted to the thumb, and the good grasping and force application are facilitated. The third transition section 216 and the fourth transition section 218 are tapered surfaces to increase mechanical strength.

The acoustic properties of the existing rope transducer and the half-wavelength transducer of this example were compared as shown in table 2. The length of the existing rope transducer is 92.8mm, the outer diameter of the rear metal block, the outer diameter of the piezoelectric crystal pile and the outer diameter of the head of the pre-tightening screw of the embodiment are the same as those of the existing rope ultrasonic transducer, the front metal block of the existing rope ultrasonic transducer is made of aluminum alloy, the rear metal block of the existing rope ultrasonic transducer is made of stainless steel, the pre-tightening screw of the existing rope ultrasonic transducer is made of titanium alloy, and the outer diameter of the front metal block of the existing rope ultrasonic transducer is the same as the maximum outer diameter of the first transition section of the embodiment. In this embodiment, the length of the flange portion is 2.7mm, the length of the first transition section is 4mm, the length of the first straight section is 7mm, the length of the second transition section is 1mm, the length of the second straight section is 9.5mm, the length of the third transition section is 1.2mm, the length of the third straight section is 1m, the length of the fourth transition section is 0.4mm, the length of the fourth straight section is 5mm, the first straight section and the second straight section have more important meanings for the resonant frequency and the amplitude gain of the transducer, and the diameter ratio of the first straight section and the second straight section approximately satisfies: phi 1/phi 2 ≈ 2, more preferably, the ratio of the diameters of the first and second flat sections is 2. In the embodiment, the maximum diameter of the flange part 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, and the outer surface of the fourth straight section is decorated with threads, wherein the thread standard is generally 4-40 UNC. The length of the piezoelectric crystal stack is 7mm, and the length of the rear metal block is 5 mm; the length of the head of the pre-tightening screw is 4 mm.

TABLE 2

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

The edge of the end face of the rear metal block 23, which is in contact with the head of the pretension screw 24, is provided with a chamfer or a fillet, so that the diameter of the circumferential surface of the rear metal block 23 is appropriately increased to form a circular ring surface with a transition step, and the rear metal block 23 can better receive the pretension force of the head of the pretension screw 24 and further improve the resonance characteristic of the ultrasonic transducer. The front end surface of the back metal block 23, namely the contact surface with the piezoelectric crystal stack 22, is a flat annular surface.

The design mode of the half-wavelength transducer 2 further reduces the size space and the weight of the ultrasonic knife, improves the use comfort and is more convenient to carry; and the acoustic characteristic is improved while the mechanical property is met, the phase tolerance of the transducer at a resonance point is increased, the matching of the transducer and a host is facilitated, and the working efficiency of the ultrasonic scalpel is improved.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "the present embodiment," "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean 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, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

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

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and simplifications made in the spirit of the present invention are intended to be included in the scope of the present invention.

Claims

1. A cordless ultrasonic knife is characterized by comprising a knife head component (1), a half-wavelength transducer (2), a handle shell (3), a circuit board (4) and a battery (5), the front end of the half-wavelength transducer (2) is in threaded connection with the cutter head component (1), 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 housing (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), the half-wavelength transducer (2) is coaxially sleeved with an anode conducting ring (6) and a cathode conducting ring (7), the positive conducting ring (6) and the negative conducting ring (7) are respectively in elastic electrical contact with the circuit board (4).

2. The cordless ultrasonic knife according to claim 1, wherein the outer peripheral surfaces of the positive conductive ring (6) and the negative conductive ring (7) are arc-shaped surfaces, a contact spherical surface (41) corresponding to the positions of the positive conductive ring (6) and the conductive ring is 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 peripheral surfaces of the positive conductive ring (6) and the negative conductive ring (7).

3. The cordless ultrasonic blade of claim 2, wherein both contact spherical surfaces (41) on the circuit board (4) are elastic surfaces, and the rigidity of the contact spherical surfaces (41) is less 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 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), the front metal block (21) is of a multi-stage variable-stage structure or a stepped structure, a threaded hole is formed in the front metal block (21) along an axis, the rear metal block (23), the piezoelectric crystal stack (22) and the front metal block (21) are sequentially coaxially sleeved on a screw rod of the pre-tightening screw (24), the screw rod of the pre-tightening screw (24) is in threaded connection with the threaded hole 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), and the end of the front metal block (21) in contact with the piezoelectric crystal stack (22) is a flange portion (211), and the outer peripheral surface of the straight section at the foremost end of the front metal block (21) is provided with threads.

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

6. The cordless ultrasonic blade of claim 5, wherein a vibration isolation ring (26) is filled between the fixing member (25) and the flange portion (211), the fixing member (25) comprises a front fixing ring (251) and a rear fixing ring (252), and the front fixing ring (251) and the rear fixing ring (252) are connected in an interference fit manner.

7. The cordless ultrasonic blade of claim 4, wherein the front metal block (21) comprises a flange portion (211), a first transition section (212), a first straight section (213), a second transition section (214) and a second straight section (215) which are connected in sequence in a direction away from the piezoelectric crystal stack (22), wherein the outer diameter of the first transition section (212) and the outer diameter of the second transition section (214) are gradually reduced in a 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 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), and the outer diameter of the second straight section (215) is the same as the minimum outer diameter of the second transition section (214), the thread is provided on an outer circumferential surface of the second straight section (215).

8. The cordless ultrasonic blade of claim 7, wherein the outer peripheral surfaces of the first transition section (212) and the second transition section (214) are both arcuate surfaces, the arcuate surface of the first transition section (212) having an arc matching the arc of a human thumb.

9. The cordless ultrasonic blade of claim 4, wherein the front metal block (21) comprises a flange portion (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 connected in sequence in a direction away from the piezoelectric crystal stack (22), wherein the outer diameter of the flange portion (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 in a direction 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 in a direction away from the piezoelectric crystal stack (22), and the outer diameter of the first straight section (213) is the same as the minimum outer diameter of the first transition section (212), the outer diameter of the second straight section (215), the minimum outer diameter of the second transition section (214) and the minimum outer diameter of the third transition section (216) are the same, the outer diameter of the third straight section (217) and the minimum outer diameter of the fourth transition section (218) are the same, the outer diameter of the fourth straight section (219) and the maximum outer diameter of the fourth transition section (218) are the same, the outer diameter of the fourth straight section (219) is smaller than the outer diameter of the second straight section (215), and the thread is provided on the outer circumferential surface of the fourth straight section (219).

10. The cordless ultrasonic blade of claim 9, wherein the outer peripheral surfaces of the first transition section (212) and the second transition section (214) are arcuate surfaces, the arc of the arcuate surface of the first transition section (212) matches the arc of a human thumb, and the outer peripheral surfaces of the third transition section (216) and the fourth transition section (218) are tapered surfaces.