Efficient sterilization method and device for metal instruments

Abstract

The invention discloses an efficient sterilization method and device for metal instruments, and belongs to the fields of medical instruments, biomedical engineering, medicine and food processing and the like. According to the heating unit, through detachable (such as a buckle type, a zipper type, an irregular shape and the like) and an inductive displacement type electromagnetic induction coil, a metal instrument is efficiently and spontaneously heated due to the eddy current effect, the heating efficiency is improved, and the heating unit can flexibly adapt to various complex application scenes. According to the invention, the eddy current effect is generated in an alternating magnetic field by using a metal body, so that high-efficiency heating is realized, the temperature rise is fast and uniform, and instruments with complex shapes are adapted by adjusting the shape of the coil; through a preset sterilization program and an automatic adjustment function, the limitation of a traditional sterilization method, such as surface sterilization, slow heat conduction speed, non-uniform heating and poor adaptability, is solved, and the method has the remarkable advantages of high efficiency, safety, low energy consumption, strong adaptability and deep sterilization.

Description

Technical Field

[0001] The present invention relates to the fields of medical devices, biomedical engineering, pharmaceuticals and food processing, and specifically to a method and device for efficiently sterilizing metal instruments by generating an eddy current effect in an alternating magnetic field, which can efficiently generate heat and thus kill pathogenic microorganisms. Background Art

[0002] Medical devices (especially surgical instruments and implants) come into direct contact with the human body, making sterilization a crucial step in preventing cross-infection. Incomplete sterilization can lead to infection, even life-threatening conditions. Similarly, food and pharmaceuticals are highly susceptible to microbial contamination during production, processing, and packaging, posing serious safety risks. Therefore, achieving comprehensive, no-dead-angle deep sterilization for large or immobile devices is crucial for ensuring the safety and stability of food and pharmaceuticals. In summary, disinfection and sterilization are crucial steps in safeguarding public health and product safety in fields such as medical devices, biomedical engineering, pharmaceuticals, and food processing, and are of irreplaceable importance.

[0003] Currently, there are four main sterilization methods for metal instruments and equipment: 1. High-temperature sterilization is a physical method that destroys microbial structures through high temperatures to achieve sterilization. High-pressure steam sterilization uses saturated steam under high pressure to generate high temperatures, causing the denaturation of microbial proteins and nucleic acids. Common parameters are 121°C for 15–30 minutes or 134°C for 3–5 minutes. It effectively kills a variety of microorganisms, including spores, and is highly efficient and reliable. However, the process is accompanied by a large amount of moisture, which may cause moisture or corrosion to metal instruments. The sterilization cycle is also long, including heating, sterilization, and cooling phases. Dry heat sterilization uses dry hot air to achieve sterilization, typically at a temperature of 160–180°C for 1–2 hours. It is suitable for moisture-sensitive instruments. The absence of moisture reduces the risk of metal rust, but prolonged high temperatures may affect the properties of some materials, and the overall processing efficiency is low.

[0004] Chemical sterilization utilizes chemicals (such as ethylene oxide and hydrogen peroxide) to kill microorganisms. It is suitable for medical devices that are vulnerable to high temperatures, high pressures, or moist heat. Ethylene oxide sterilization is non-corrosive to metals and can penetrate complex structures, but requires a long sterilization cycle (hours to days), is toxic and carcinogenic, and requires adequate ventilation to remove residual material. Hydrogen peroxide plasma sterilization has a short cycle (30 to 60 minutes) and leaves no toxic residue, but its penetration is limited, making it suitable for devices with simple structures or open packaging. Glutaraldehyde and o-phthalaldehyde are commonly used for high-level disinfection and are suitable for heat-sensitive metal instruments such as endoscopes. The former requires prolonged immersion and is irritating, while the latter is faster-acting and less irritating, but requires thorough rinsing after use. Peracetic acid has a rapid bactericidal effect but is corrosive to some metals, so material compatibility must be assessed before use.

[0005] 3. Radiation sterilization uses high-energy radiation (such as gamma rays, electron beams, and X-rays) to destroy the DNA or RNA structures of microorganisms, achieving efficient sterilization. Gamma rays, emitted by radioactive isotopes (such as cobalt-60), offer strong penetrating power and are suitable for large quantities and high-density items. However, they carry radiation safety risks, the need to manage radioactive sources that cannot be shut down, and the potential for impact on material properties. Electron beam sterilization utilizes an accelerator to generate a high-energy electron beam, offering rapid sterilization without residual radioactivity. It is suitable for heat-sensitive materials, but its penetrating power is limited, making it suitable only for surface or thin-layer products. X-ray sterilization, generated by a high-energy electron beam striking a target, combines excellent penetrating power with a controllable radiation source. It is suitable for well-packaged medium-density items, but the system is complex and costly. Currently, all three methods require specialized equipment, limiting their applicability and facing technical and economic challenges for widespread adoption.

[0006] 4. Low-temperature sterilization: Hydrogen peroxide low-temperature plasma sterilization is suitable for heat-sensitive metal instruments. It has the advantages of fast sterilization speed, no toxic residue, low temperature and low humidity, but it has disadvantages such as poor penetration, strong oxidizing properties, high cost and high loading requirements.

[0007] At present, sterilization mainly relies on the treatment of the instrument surface, but traditional methods have many limitations. On the one hand, liquid or gas heat conduction sterilization is slow, especially when dealing with large or thick-walled metal instruments, the heat transfer is uneven, time-consuming, and inefficient. On the other hand, for instruments with complex shapes, slender pipes or internal cavities, it is difficult for liquids or gases to fully contact all surfaces, which can easily lead to sterilization dead corners. In addition, large fixed equipment is difficult to sterilize using existing methods due to its large size and fixed position. With the rapid development of the medical device, food and pharmaceutical processing industries, traditional technologies can no longer meet the needs of complex scenarios, and there is an urgent need to develop more efficient, flexible and adaptable sterilization methods.

[0008] Biomedical implants carry a risk of infection both during and after implantation. Traditional antimicrobial strategies include systemic antibiotic use, surface antimicrobial coatings, surgical debridement, and implant removal or replacement. However, these methods all have significant limitations: the misuse of antibiotics can easily lead to increased bacterial resistance, significantly reducing the effectiveness of treatment; antimicrobial coatings can cause local side effects, affect tissue healing, and are prone to failure due to wear; and surgical debridement and implant replacement are not only traumatic but may also cause secondary infection. Therefore, there is an urgent need to develop an efficient, controllable sterilization method and supporting devices that are applicable to both in vitro and in vivo metal instruments to improve infection prevention and control and reduce the burden of treatment on patients.

[0009] In principle, sterilization methods based on magnetothermal mechanisms show great potential in multiple fields. Magnetothermal heat generation can be attributed to the conversion of energy losses in a medium into heat in an alternating magnetic field. The main mechanisms include magnetization relaxation, hysteresis loss, and eddy current loss. For magnetic particles ranging in size from nanometers to micrometers, heat generation occurs primarily through magnetization relaxation and hysteresis. For highly conductive metal materials measuring millimeters and larger, eddy currents dominate, resulting in strong induced currents, high heat generation efficiency, and rapid temperature rise. Metallic materials commonly used in medical devices, biomedical engineering, pharmaceuticals, and food processing (such as pure titanium, titanium alloys, magnesium alloys, aluminum alloys, and cobalt-chromium alloys) possess excellent electrical conductivity and structural dimensions, making them suitable for efficient heating in alternating magnetic fields via eddy currents. Therefore, this strategy not only overcomes the limitations of traditional sterilization methods in terms of heat sensitivity, material compatibility, and residual toxicity, but also provides a new, efficient, safe, and flexible sterilization solution for a variety of applications.

[0010] A literature search of prior art revealed Chinese patent application number 201711133143.X, entitled "A Medical Device High-Temperature Sterilization System and Method Thereof." The patent describes itself as follows: "A medical device high-temperature sterilization system and method thereof, comprising a medical device and a sterilization chamber, wherein the sterilization chamber has a sterilization chamber with a positioning assembly and a heating assembly." This patent achieves sterilization by conducting heat to the medical device through a heat conductor, improving sterilization efficiency. However, its applicability to medical devices is limited, requiring conformity to pre-set positioning holes. Contact between the heat conductor and the device can still result in incomplete localized sterilization, especially for devices with complex shapes. Another Chinese patent application number is 201711133152.9, entitled "A Medical Device Ionizing Radiation Sterilization System and Method Thereof." This patent includes a medical device, an infrared scanning chamber, an ionizing sterilization chamber, and its controller. An infrared sensor scans the medical device's model information, generating corresponding sterilization instructions, which are then precisely sterilized by an ionizing emitter. However, the invention uses bone or cesium as a radiation source, which raises the issue of radioactive material management and may increase operational complexity and cost. Furthermore, the scanning step and the sterilization step are separated, which may affect sterilization efficiency.

[0011] The Chinese patent application number is 202210880088.5, and its name is: Infrared-visible light photothermal and photodynamic synergistic low-temperature antibacterial dental implant material. The invention "relates to a photothermal and photodynamic synergistic low-temperature antibacterial dental implant with infrared-visible light and a preparation method thereof. The material consists of a pure titanium matrix and a PDA-Cu2O / TNT coating. The TNT is generated in situ on the surface of the matrix by anodic oxidation, and Cu2O is combined with TNT by electrodeposition to form a heterojunction, and then the PDA deposited thereon controls the release of copper elements, giving the implant excellent light-responsive antibacterial properties and good bone regeneration-promoting function." After the implant is coated, the invention exhibits antibacterial properties under visible light and near-infrared light conditions, but the preparation process of the material coating is relatively complicated, and there may be side effects and safety hazards, and it cannot be widely used in clinical practice.

[0012] Chinese patent application number 200510030112.2, titled "Tumor Alternating Magnetic Field Hyperthermia System," describes itself as follows: "A tumor alternating magnetic field hyperthermia system in the field of medical device technology. The invention comprises an alternating power supply system, a magnetic field generating system, a magnetic circuit system, a hyperthermia temperature measurement and feedback system, an alternating magnetic field intensity measurement and feedback system, a treatment bed system, a shielding system, and a central operation and control system." The core principle of this invention is the hysteresis effect of the alternating magnetic field. Using a magnetic conductor, the alternating magnetic field is concentrated into the air gap region, causing the ferromagnetic material implanted in the tumor to generate heat, thereby killing tumor cells and improving the efficacy and safety of the hyperthermia treatment. Chinese patent application number 200910157849.9, titled "Magnetic Induction Therapy Machine," describes itself as "relating to the field of magnetic induction therapy for tumors, and particularly to a magnetic induction therapy machine for treating tumor diseases." While magnetic material is artificially implanted into tumor tissue, under the influence of an external alternating magnetic field, the magnetic material cuts through the alternating magnetic field lines, generating alternating currents. These eddy currents generate heat energy in the magnetic material, heating the tumor tissue and killing tumor cells. The disadvantage of both methods is that they require prior intervention and implantation of ferromagnetic materials into the tumor site, which increases the complexity of the operation. Summary of the Invention

[0013] To address the deficiencies in the prior art, the present invention discloses a highly efficient sterilization method and device for metal instruments. This method utilizes the eddy current effect of a metal medium in an alternating magnetic field to cause the metal medium to generate heat efficiently, thereby killing pathogenic microorganisms. This method achieves the purpose of simply and efficiently killing bacteria without the need to introduce any reagents or materials. The technical solution is as follows: A high-efficiency sterilization device for metal instruments, comprising the following units: Alternating power supply unit: The input end is connected to external standard AC power, which is converted into an alternating current with a frequency of 10 kHz to 1000 kHz, which is used to drive the coil to generate an alternating magnetic field. The output end is connected to the magnetic field generating unit. The alternating power supply unit adjusts the frequency and intensity of the output current through PWM modulation technology to control the heat generation efficiency of the eddy current effect; Magnetic field generating unit: The input end receives alternating current and outputs alternating magnetic fields of different strengths to the heating unit; the magnetic field generating unit includes a multi-speed coil turns switching module for adjusting the coil turns according to the target magnetic field strength; Heating unit: Contains a detachable, inductively shifted electromagnetic induction coil. The coil uses multi-layer copper windings, is covered with a high-temperature resistant polyimide insulation layer, and has a quick-plug interface to adapt to metal instruments of various sizes and shapes. When a metal instrument is placed in the coil, the alternating magnetic field causes eddy currents to be generated inside the coil, causing it to self-heat. Temperature monitoring unit: uses optical fiber temperature sensors, infrared thermal imagers and other technologies to monitor the local temperature distribution of metal equipment in real time. It has a built-in PID algorithm controller to dynamically adjust the local temperature, and the output end is connected to the central control unit. Circulating water cooling temperature control unit: The magnetic field generating unit and the heating unit are connected through pipes, and cold water circulates in the pipes to ensure that the temperature of the device is stable at 25±1℃; Central control unit: connected to each unit via a data cable, with an integrated touch screen operation interface and a built-in material database; the database stores the resistivity, magnetic permeability and safety temperature threshold parameters of titanium alloy, stainless steel and cobalt-chromium alloy, and is equipped with a matching algorithm to automatically calculate and set the alternating frequency, magnetic field strength and sterilization time based on the instrument material input by the user or the scanned barcode information; the central control unit is also equipped with a magnetic field adjustment module to eliminate temperature unevenness of metal instruments by independently controlling the position of the coil, and to adjust the alternating current to change the magnetic field strength, thereby eliminating the deviation between the real-time temperature of the metal instrument and the preset target temperature.

[0014] Preferably, the frequency range of the alternating current output by the alternating power supply unit is 10 kHz to 1000 kHz.

[0015] Preferably, the electromagnetic induction coil of the heating unit is a detachable, inductively movable structure adapted to metal instruments of different shapes and sizes.

[0016] Preferably, the circulating water cooling temperature control unit cools down key parts of the device such as the electromagnetic coil through cold water circulation, thereby ensuring the temperature stability of the magnetic field generating unit and the heating unit.

[0017] Preferably, the central control unit presets a plurality of sterilization programs, each targeting at the sterilization requirements of different metal materials.

[0018] The present invention also discloses a high-temperature sterilization method for metal instruments, comprising the following steps: Step S1: Instrument loading and material identification Place the metal instrument in the electromagnetic induction coil of the heating unit, select the instrument material through the touch screen of the central control unit or scan the instrument barcode to call the parameters in the built-in material database; Among them, material identification technology: the barcode uses a label or QR code with embedded device material, size, and batch information, and the scanning accuracy is ≥99.9%.

[0019] If you select the material manually, the touch screen provides a visual material library (including icons and physical properties of titanium alloy, stainless steel, and cobalt-chromium alloy).

[0020] Fault-tolerance mechanism: If the scan fails or the material does not match, the system automatically starts the infrared spectrum analysis module and matches the database through the reflection spectrum characteristics.

[0021] Database scalability: supports user-defined new materials (such as magnesium alloys) by inputting resistivity ( ρ )、heat capacity( C ) and other parameters to generate a matching program.

[0022] Step S2: Parameter matching and program startup Adaptive learning: The system records each sterilization data (such as actual heating rate and temperature difference), optimizes preset parameters through artificial intelligence algorithms, and improves subsequent matching accuracy.

[0023] Step S3: Dynamic sterilization and temperature control The alternating power supply unit outputs high-frequency, low-voltage, high-current alternating current to the magnetic field generating unit, generating an alternating magnetic field that causes the metal instrument to self-heat. The temperature monitoring unit provides real-time feedback of local temperature data, and the central control unit initiates magnetic field regulation to dynamically adjust the temperature. If the temperature monitoring unit shows that the temperature difference at different positions of the metal instrument exceeds a threshold, the central control unit adjusts the coil position to change the magnetic field strength in that area.

[0024] If the temperature monitoring unit shows that the deviation between the real-time temperature of the metal instrument and the target temperature exceeds a set threshold, the central control unit adjusts the magnitude of the alternating current to change the magnetic field strength.

[0025] Response to extreme scenarios: If the deviation between the real-time temperature of the metal instrument and the target temperature exceeds the safety threshold, the system will automatically power off, stop the alternating current output, and suspend heating.

[0026] Step S4: Safety protection and cooling Cold water circulates through the pipes of the circulating water cooling temperature control unit to maintain the device temperature ≤25°C; if the device temperature exceeds the safety threshold, the central control unit triggers frequency reduction or emergency shutdown; Emergency shutdown and reset: After shutdown, the cause of the fault (such as overtemperature, insufficient water level) needs to be manually confirmed. After reset, the system automatically performs the self-test procedure (coil impedance detection, sensor calibration).

[0027] Stability verification: 24-hour continuous operation test shows that the temperature fluctuation is ≤±2℃.

[0028] Step S5: Sterilization completion and data recording After the preset sterilization time is reached, heating will automatically stop and a sterilization report will be generated, recording the temperature curve, energy consumption and microbial inactivation rate (ATP test > 99.99%).

[0029] Preferably, the sterilization temperature threshold is 121°C for 20 minutes, or 134°C for 5 minutes.

[0030] The central control unit automatically matches the sterilization program to the material type of the metal instrument, including preset parameters for titanium alloy, stainless steel, and cobalt-chromium alloy. Fiber optic temperature sensors and infrared thermal imagers monitor the local temperature uniformity of the metal instrument. If the temperature difference exceeds a set threshold, the central control unit automatically adjusts the magnetic field distribution to eliminate thermal unevenness.

[0031] According to the above-mentioned high-efficiency sterilization device for metal instruments, or according to the above-mentioned sterilization method, the metal instrument is an implant in the body, including a hip joint prosthesis, a heart stent or an oral implant, and is immediately sterilized by a detachable electromagnetic induction coil during the implantation surgery, and the sterilization time is ≤60 minutes.

[0032] According to the above-mentioned high-efficiency sterilization device for metal instruments, or according to the above-mentioned sterilization method, the metal instruments are surgical instruments, orthopedic implants, dental drills or endoscopes, which are used to kill surface and internal pathogenic microorganisms. After sterilization, the microbial inactivation rate is ≥99.99%, and the instruments have no thermal damage or chemical residues.

[0033] According to the above-mentioned high-efficiency sterilization device for metal instruments, or according to the above-mentioned sterilization method, the metal instruments are metal containers, pipes or cutters in a food processing production line, and rapid sterilization is achieved through the eddy current effect of the alternating magnetic field. The sterilization temperature threshold is 100-200°C, and the sterilization time is ≤60 minutes; the metal instruments are instruments with slender pipes, internal cavities or special-shaped structures, and local temperature differences are eliminated by adjusting the magnetic field distribution to ensure that the temperature uniformity deviation of the internal cavity is less than the set threshold.

[0034] Beneficial effects

[0035] High efficiency: The heat generation efficiency based on the magnetocaloric effect is high, which can quickly increase the local temperature, significantly shorten the sterilization time, and effectively kill pathogenic microorganisms.

[0036] Flexibility: The heating unit can adopt different design structures according to different application scenarios, which solves the limitations of traditional fixed sterilization devices and can be used in both in vitro and in vivo environments.

[0037] Intelligent control: Temperature monitoring ensures temperature control within a safe range to avoid damage to equipment. Combined with a central control unit, this system enables intelligent operation throughout the entire process, improving safety and reliability.

[0038] Safety: Compared with chemical disinfection, there is no chemical residue after sterilization, which avoids corrosion to operators.

[0039] Wide applicability: It is suitable for a variety of metal instruments, such as titanium alloy, stainless steel, etc., to avoid corrosion or damage to metal instruments or equipment, and has broad application prospects.

[0040] Cost: Compared with large-scale disinfection and sterilization devices, the magnetothermal effect in this device acts directly on metal instruments, reducing energy loss and having lower costs in terms of equipment investment, energy consumption and maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Schematic diagram of the high-temperature sterilization device for metal instruments of the present invention. DETAILED DESCRIPTION

[0042] The invention is based on the physical phenomenon that metal media generate eddy current effect in an alternating magnetic field. When a metal medium is placed in an alternating magnetic field, the change in the magnetic field induces eddy current inside the medium, thereby causing the local temperature of the metal medium to rise.

[0043] The present invention is achieved through the following technical solutions, including the following units: Alternating current power supply unit: The power input terminal is connected to an external standard alternating current via a wire, converting it into a high-frequency, low-voltage, high-current alternating current. The power output terminal is connected to the magnetic field generating unit, outputting the alternating current to the magnetic field generating unit. The alternating current power supply unit converts the external standard alternating current into a high-frequency, low-voltage, high-current alternating current. By adjusting the frequency and intensity of the current, the heat generation efficiency and electric field strength of the eddy current effect are controlled.

[0044] Magnetic Field Generator: The power input is connected to the AC power supply unit via a wire, receiving alternating current and converting it into alternating magnetic field for output to the heating unit. The magnetic field generator generates an alternating magnetic field, the intensity of which can be adjusted as needed to ensure sufficient eddy currents are generated within the magnetic field for metal instruments. The alternating power supply unit's PWM modulation technology adjusts the current frequency, combined with the magnetic field generator unit's coil turns switching (e.g., multi-speed selection) to achieve variable magnetic field intensities.

[0045] Heating unit: connected to the magnetic field generating unit, composed of an electromagnetic induction coil. The rate of change of the alternating magnetic field depends on the diameter of the coil. The smaller the diameter, the faster the rate of change of the magnetic field, and the greater the induced electromotive force and eddy current. This unit can be replaced with different electromagnetic induction coils as needed: when the coil is integrated, metal instruments can be placed in it; the detachable coil can be flexibly assembled according to the special structure of the instrument. The function of the heating unit is to connect the alternating magnetic field. When the alternating magnetic field acts on the metal medium, eddy currents are generated inside the medium, causing the local temperature to rise. The coil adopts multi-layer copper winding, and the outer layer is covered with high-temperature resistant insulating material (such as polyimide). The detachable interface is a snap-on structure, a zipper structure, an irregular shape, etc., which is suitable for instruments of different sizes and shapes.

[0046] Temperature Monitoring Unit: The input side measures the local temperature using methods such as fiber optic temperature sensors and infrared thermal imagers. The output side transmits this temperature data to the central control unit through a feedback mechanism. The temperature monitoring unit measures the temperature of the metal object in real time and transmits this data to the central control unit for real-time monitoring and adjustment, ensuring that the temperature is controlled within a safe, stable, and effective range.

[0047] The circulating water-cooled temperature control unit: The input is connected to an external power source, and the output is connected to the magnetic field generating unit and the heating unit via pipes. It also features a water inlet, outlet, and level sensor. The level sensor signal is transmitted to the central control unit via a feedback mechanism. When the water level falls below the specified level, water is automatically replenished. Replenishment stops when the water level reaches the maximum, ensuring stable operation. The circulating water-cooled temperature control unit cools the magnetic field generating unit and the heating unit to prevent overheating.

[0048] Central Control Unit: The central control unit is the control center of the sterilization device. It integrates an industrial-grade processor and supports multi-threaded computing, enabling rapid database access and real-time parameter adjustment. The hardware device consists of an operation panel and an electronic computer equipped with integrated control software. It is connected to the alternating power supply unit, magnetic field generating unit, temperature monitoring unit, and circulating water cooling temperature control unit via sensors and control lines, obtaining real-time feedback data from these units and adjusting the device via control lines. The operation panel is designed as a touch screen for setting sterilization parameters, including current intensity, operating time, circulating water cooling temperature, etc., and displays feedback data from each unit to monitor operating status. It can also preset multiple sterilization programs suitable for different types of metal instruments, and record and save data for subsequent analysis and optimization. The integrated control software is developed using a professional measurement and control software platform.

[0049] The central control unit integrates three levels of safety protection: ① When the deviation between the real-time temperature of the metal instrument and the target temperature exceeds the set threshold, the current regulation is triggered and the magnetic field strength is changed; ② When the deviation between the real-time temperature of the metal instrument and the target temperature exceeds the safety threshold, the power supply is automatically cut off; ③ When the liquid level is lower than the minimum water level, the operation is suspended and an alarm is issued.

[0050] The central control unit has a built-in material database that automatically matches the frequency, magnetic field strength and sterilization time according to the material of the instrument.

[0051] Construction of material database and logical matching mechanism: Database content: The central control unit's built-in material database stores the physical property parameters of various metal materials, including: resistivity (determines the efficiency of eddy current heat generation); heat capacity and thermal conductivity (determine the heating rate and uniformity); and safe temperature threshold (to prevent material oxidation or deformation).

[0052] Example 1: Sterilization of titanium alloy implants, taking orthopedic bone screws as an example: Material identification: The operator selects "titanium alloy" through the touch screen or scans the instrument barcode, and the central control unit calls the titanium alloy parameters in the database; Parameter matching: The database automatically matches the preset program: frequency 100 kHz, alternating current 1-10 A, target temperature 121°C, sterilization time 15 minutes; Dynamic adjustment: The temperature monitoring unit provides real-time feedback data. If the local temperature difference is ±5°C, the central control unit will adjust the displacement of the electromagnetic coil to make the temperature distribution uniform. Safety protection: If the temperature exceeds 134°C (safety threshold), frequency reduction or shutdown is triggered.

[0053] Example 2: Sterilization of stainless steel surgical instruments, taking stainless steel tweezers as an example: Parameter matching: stainless steel, frequency 100 kHz, alternating current 1-10 A, target temperature 121°C, duration 15 minutes; Dynamic adjustment: The temperature monitoring unit provides real-time feedback data. If the local temperature difference is ±5°C, the central control unit will adjust the displacement of the electromagnetic coil to make the temperature distribution uniform. Effect: The temperature reaches the target value within 3 minutes, with a temperature difference of ±2°C. ATP testing shows a microbial inactivation rate of >99.99%, and the instrument does not change color.

[0054] Example 3: Chairside sterilization during implant surgery, taking oral implant surgery as an example: Application description: During oral implant surgery, after the implant is placed in the alveolar bone, the heating unit is replaced with an electromagnetic coil suitable for the head for chairside sterilization to kill pathogenic microorganisms that may be introduced during the implant surgery.

[0055] Parameter matching: titanium alloy, frequency 100 kHz, alternating current 1-10 A, target temperature 50°C, duration 4 minutes; Dynamic adjustment: When the temperature monitoring unit detects a temperature deviation of ±5°C at the implant tip, the central control unit reduces the current and adjusts the temperature difference to ±2°C; Effect verification: There is no sign of infection in the tissues around the implant.

[0056] Example 4: Multiple sterilization treatments of metal implants before, during, and after surgery, taking hip replacement surgery as an example: Application description: Before, during and after the implantation of metal implants, the heating unit is replaced with an electromagnetic coil suitable for local areas to perform multiple sterilization treatments before, during and after the operation.

[0057] Application scenario: Instant sterilization of cobalt-chromium alloy implants during hip replacement surgery.

[0058] Parameter matching: frequency 20 kHz, alternating current 0.1-5 A, target temperature 50°C, duration 3 minutes; Dynamic adjustment: The temperature monitoring unit detects the internal cavity temperature difference of ±5℃; Effect verification: There is no sign of infection in the tissues around the implant.

[0059] This invention utilizes the eddy current effect of metal instruments in an alternating magnetic field to efficiently generate heat, achieving simple and effective bacterial destruction without the need for any additional bactericidal substances. The magnetocaloric coils designed in this device, connected to the alternating magnetic field, offer flexible assembly and disassembly, adjustable dimensions, and are suitable for complex and uniquely shaped instruments, encompassing a wide range of applications.

[0060] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-efficiency sterilization device for metal instruments, characterized in that: The following units are included: Alternating power supply unit: The input end is connected to an external standard alternating current, which is converted into a high-frequency, low-voltage, high-current alternating current for driving the coil to generate an alternating magnetic field. The output end is connected to the magnetic field generating unit. The alternating power supply unit uses PWM modulation technology to adjust the frequency and intensity of the output alternating current to control the heat generation efficiency of the eddy current effect. Magnetic field generating unit: The input end receives alternating current and outputs alternating magnetic fields of different magnetic field strengths to the heating unit; the magnetic field generating unit includes a multi-speed coil diameter switching module for adjusting the coil diameter according to the target magnetic field strength; Heating unit: Contains a detachable, inductively shiftable electromagnetic induction coil. The coil uses multi-layer copper windings, is covered with a high-temperature resistant insulation layer, and is equipped with a quick-plug interface to adapt to metal instruments of different diameters and shapes, as well as heavy and difficult-to-shift metal instruments. When a metal instrument is placed in the coil, the alternating magnetic field induces eddy currents inside it, causing it to self-heat. Temperature monitoring unit: This unit uses fiber optic temperature sensors and infrared thermal imagers to monitor the local temperature distribution of metal instruments in real time. A built-in PID algorithm controller dynamically adjusts the alternating current based on the deviation between the real-time temperature feedback value and the preset target temperature. The output terminal transmits the processed control signal to the central control unit in real time. Circulating water cooling temperature control unit: connect the magnetic field generating unit and the heating unit through pipes to guide the cold water circulation to the electromagnetic coil; Central control unit: connected to each unit via a data cable, with an integrated touch screen operation interface and a built-in material database; the central control unit adjusts the magnetic field according to temperature feedback and adjusts the magnetic field strength by adjusting the coil position and current.

2. The metal instrument high-efficiency sterilization device according to claim 1, characterized in that: The database stores the resistivity and safety temperature threshold parameters of titanium alloy, stainless steel, and cobalt-chromium alloy, and is configured with a matching algorithm to automatically calculate and set the alternating frequency, magnetic field strength, and sterilization time based on the instrument material input by the user or the scanned barcode information; the database supports users to customize the addition of new material parameters, including resistivity and safety temperature threshold, and automatically generates a matching program after input through the touch screen.

3. The metal instrument high-efficiency sterilization device according to claim 1, characterized in that: The electromagnetic induction coil of the heating unit is a detachable and inductively displaceable structure, and is suitable for metal instruments of different shapes and sizes.

4. The metal instrument high-efficiency sterilization device according to claim 1, characterized in that: The circulating water cooling temperature control unit circulates cooling water to the electromagnetic coil tube to ensure the temperature stability of the magnetic field generating unit and the heating unit.

5. The metal instrument high-efficiency sterilization device according to claim 1, characterized in that: The central control unit has preset multiple sterilization programs to meet the sterilization requirements of different metal materials.

6. A high-temperature sterilization method for metal instruments, based on the metal instrument high-efficiency sterilization device according to claim 1, characterized in that: The following steps are involved: Step S1: Instrument loading and material identification; Place the metal instrument in the electromagnetic induction coil of the heating unit, select the instrument material through the touch screen of the central control unit or scan the instrument barcode to call the parameters in the built-in material database; Step S2: parameter matching and program startup; Step S3: Dynamic sterilization and temperature control: The alternating power supply unit outputs alternating current to the magnetic field generating unit, generating an alternating magnetic field that causes the metal instrument to self-heat. The temperature monitoring unit provides real-time feedback of local temperature data and performs temperature control using a PID algorithm. If the temperature difference between different parts of the metal instrument exceeds a set threshold, the central control unit activates magnetic field regulation, causing the electromagnetic induction coil to shift inductively to eliminate temperature unevenness. If the deviation between the real-time temperature of the metal instrument and the preset target temperature exceeds a set threshold, the central control unit activates magnetic field regulation, changing the intensity of the alternating magnetic field by adjusting the magnitude of the alternating current. Step S4: Safety protection and cooling: The circulating water cooling temperature control unit maintains the device temperature below a certain temperature through cold water circulation; if the device temperature exceeds the safety threshold, the central control unit triggers frequency reduction or emergency shutdown; Step S5: Sterilization completion and data recording: After the preset sterilization time is reached, heating is automatically stopped and a sterilization report is generated, recording the temperature curve, energy consumption and microbial inactivation rate.

7. The high-temperature sterilization method for metal instruments according to claim 6, characterized in that: The local temperature uniformity of metal instruments is monitored through fiber optic temperature sensors and infrared thermal imagers. If the temperature difference exceeds the set threshold, the central control unit automatically adjusts the magnetic field distribution to eliminate thermal unevenness; the central control unit immediately starts magnetic field adjustment after detecting that the temperature difference exceeds the limit.

8. The high-temperature sterilization method for metal instruments according to any one of claims 6 to 7, characterized in that: The metal instrument is an implant in the body, including a hip joint prosthesis, a heart stent or an oral implant, and is immediately sterilized by a detachable electromagnetic induction coil during and after the implantation operation, with the sterilization time being ≤60 minutes.

9. The high-temperature sterilization method for metal instruments according to any one of claims 6-7, characterized in that: The metal instrument is a surgical instrument, orthopedic implant, dental drill or endoscope, which is used to kill pathogenic microorganisms on the surface and inside. After sterilization, the microbial inactivation rate is ≥99.99%, and the instrument has no thermal damage or chemical residue.

10. The high-temperature sterilization method for metal instruments according to any one of claims 6 to 7, characterized in that: The metal instrument is a metal container, pipe or cutter in a pharmaceutical or food processing production line, and is rapidly sterilized through the eddy current effect of an alternating magnetic field. The sterilization temperature threshold is 100-200°C, and the sterilization time is ≤60 minutes. The metal instrument is an instrument with a slender pipe, an internal cavity or an irregular structure. The local temperature difference is dynamically eliminated through magnetic field adjustment to ensure that the temperature uniformity deviation of the internal cavity is less than the set threshold.

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