Mixing method and device for blood culture bottle with rotor

Abstract

The invention belongs to the technical field of medical apparatus and instruments, and discloses a mixing method and device for a blood culture bottle with a rotor, and the method comprises the following steps: assembling a mixing device, and setting initialization parameters; starting an electromagnet to drive a magnetic piece rotor to rotate, and monitoring the liquid condition in the mixing period; performing data decision and parameter adjustment according to the monitoring condition; and circularly executing until the culture is finished. The shaking of the culture solution in the blood culture bottle and the shaking amplitude can be actively controlled, the gas flow and the dissolved oxygen degree in the blood culture bottle are increased, the growth of bacteria is promoted, the incubation detection time of the bacteria is remarkably shortened, and the clinical detection and diagnosis efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a mixing method and apparatus for blood culture bottles with a rotor. Background Technology

[0002] The fully automated blood culture instrument is a microbiological testing device used to test whether bacteria are present in blood samples. It plays a very important role in rapidly detecting whether bacteria are growing in the blood of patients with sepsis or bacteremia, which are clinically life-threatening conditions, in order to make a definitive diagnosis.

[0003] Current fully automated blood culture instruments use a single motor to simultaneously agitate multiple culture and testing stations. To ensure mass transfer and system homogeneity in the culture medium, the mechanical agitation is generally slow, resulting in low dissolved oxygen levels. Furthermore, since multiple culture samples are placed in the culture and testing stations simultaneously, the oxygen requirements of bacteria in different samples vary. Uniform, slow mechanical agitation cannot meet the oxygen requirements of bacteria in some culture samples, leading to long incubation times for some bacterial species, requiring 2-4 weeks or even longer to be detected (such as dimorphic fungi), which seriously affects the efficiency of clinical testing and diagnosis.

[0004] Furthermore, although there are currently publicly available technical solutions for controlling mixing using magnetic fields, these mainly involve continuous rotation. While continuous rotation of the magnetic rotor increases dissolved oxygen levels, the rotational state can interfere with optical detection (such as turbidity and fluorescence analysis), leading to a decrease in detection accuracy. In addition, existing technologies also disclose adjusting the magnetic field strength only based on CO2 concentration, without considering changes in the viscosity of the culture medium (such as decreased fluidity due to blood coagulation) and the different stages of microbial growth (different stages have different dissolved oxygen requirements), which can also affect the mixing accuracy.

[0005] Therefore, there is a need to design a blood culture mixing method and apparatus that can solve the above problems. Summary of the Invention

[0006] The present invention aims to address the technical problems existing in the background art by providing a mixing method and apparatus for a blood culture bottle with a rotor, which can actively control the rotation rate of the culture medium in the blood culture bottle, increase the gas flow and dissolved oxygen in the blood culture bottle, promote bacterial growth, significantly shorten the bacterial incubation and detection time, and accelerate the efficiency of clinical detection and diagnosis.

[0007] To achieve the above technical objectives, the present invention adopts the following technical solution:

[0008] A mixing method for blood culture bottles with a rotor includes the following steps: Step 1: Assemble the mixing device and set the initialization parameters; Step 2: Start the electromagnet to drive the magnetic rotor to rotate and monitor the liquid condition during the mixing cycle; Step 3: Make data decisions and adjust parameters based on the monitoring results; Step 4: Repeat the process until the culture is completed.

[0009] Based on the above technical solution, further, in step 1, setting the initialization parameters includes:

[0010] (1) Set the duration of the mixing period T1 and the duration of the quiescent period T2;

[0011] (2) Set the active damping current parameters of the electromagnet: reverse pulse width t≤10ms, pulse amplitude I=1.5×operating current; (3) Configure the sensor trigger delay time t d = 0.5 seconds;

[0012] (4) Base speed setting:

[0013] Retention period: ω_base = 500 RPM;

[0014] Logarithmic period: ω_base = 1000 RPM;

[0015] Plateau period: ω_base = 600 RPM.

[0016] Based on the above technical solution, further, in step 2, the mixing cycle includes a first stage; and the first stage is the mixing period, the monitoring process of which is as follows:

[0017] a) When three-phase alternating current is applied to the electromagnet, the current I = I_max, which drives the magnetic rotor to rotate at a high speed of 1200 RPM.

[0018] b) Monitor rotor speed in real time and maintain speed fluctuation ≤ ±5%;

[0019] c) Record the end time t1 of the mixing period.

[0020] Based on the above technical solution, furthermore, in step 2, the mixing cycle also includes a second stage; and the second stage is a static period, the monitoring process of which is as follows:

[0021] d) Cut off the main current of the electromagnet at time t1;

[0022] e) and immediately apply a reverse damping pulse;

[0023] f) After a set delay time, the infrared sensor is activated to detect the CO2 concentration P and the rate of change V;

[0024] g) Collect turbidity and temperature data simultaneously.

[0025] Based on the above technical solution, further, during the stationary period, impedance analysis is also used to monitor the liquid viscosity, and the monitoring process is as follows:

[0026] 1) Superimpose a 10 kHz high-frequency detection signal on the working current of the electromagnet;

[0027] 2) Sample the phase difference Δφ of the coil voltage and calculate the viscosity η = K·Δφ, where K is the calibration coefficient;

[0028] 3) If η > 15 mPa·s, trigger the viscosity compensation mechanism.

[0029] Based on the above technical solution, further, the viscosity compensation mechanism is as follows:

[0030] If η > 15 mPa·s, then ω_adj = ω_base×(1 + 0.3×(η - 15) / 10); where ω_adj is the actual output speed after viscosity compensation, and the unit is RPM.

[0031] Based on the above technical solution, further, the viscosity compensation mode includes a continuous rotation mode. In the continuous rotation mode, η ≤ 25 mPa·s:

[0032] A) Calculate the PWM duty cycle D = ω_adj / ω_max×100% according to ω_adj;

[0033] B) Output three-phase PWM current by the H-bridge to drive the rotor to rotate unidirectionally.

[0034] Based on the above technical solution, further, the viscosity compensation mode also includes a swing mode. In the swing mode, η > 25 mPa·s:

[0035] C) Control the electromagnetic rotor to swing reciprocally within the range of ±30°;

[0036] D) The swing frequency f = 2 Hz; <​​​​​​​​​​

[0041] When it is the plateau period, if the CO2 concentration P > threshold P0 and V < V0: then set the current I = 0.3I_max and the rotation speed 400 RPM during the mixing period of the next cycle.

[0042] Step 32: Compensate for detection interference according to turbidity data: If the turbidity fluctuation > threshold ΔNTU, then extend the stationary period T2' = T2 + 30 seconds.

[0043] A mixing device for a blood culture bottle with a rotor, comprising a box body, a blood culture bottle with a magnetic part rotor, and a cultivation and detection seat. A number of cultivation and detection seats are arranged in the box body, and a number of unit cavities are arranged on the cultivation and detection seat. The blood culture bottle is placed in the unit cavity; at least one magnetic part rotor is arranged in the blood culture bottle; a magnetic field generating device is arranged outside the blood culture bottle, and the magnetic field generated by the magnetic field generating device drives the magnetic part rotor to rotate in the blood culture bottle, thereby driving the culture solution in the blood culture bottle to rotate to form a vortex, increasing the dissolved oxygen of the culture solution.

[0044] Compared with the prior art, the beneficial effects produced by the present invention are:

[0045] (1) The present invention replaces the existing inversion mixing and continuous rotation mixing schemes with a scheme of controlling the mixing of the magnetic part rotor. It can not only effectively improve the mixing effect, protect the mixing structure or device, extend its service life, but also solve the contradiction of continuous rotation interfering with detection through the "rotation - stationary alternation" mode and coordinated control with detection. Moreover, through time - sequence segmentation, the "mixing - detection" dual - function optimization is realized. Without adding new hardware, only the control algorithm needs to be modified, which is suitable for the upgrade of existing blood culture instruments and the cost is controllable.

[0046] (2) The blood culture bottle device with a rotor provided by the present invention is based on the existing fully automatic blood culture instrument. Remove the mechanical shaking device, set an electromagnet on one side of the unit cavity of the cultivation and detection seat, and place a magnetic part rotor in the blood culture bottle inserted into the unit cavity. When the electromagnet is powered on, an external magnetic field is generated, driving the magnetic part rotor in the blood culture bottle to rotate at a high speed, thereby driving the culture solution in the blood culture bottle to rotate to form a vortex, so that the oxygen in the blood culture bottle can be fully integrated with the culture solution, improving the dissolved oxygen of oxygen. And the current can be adjusted and the magnetic field intensity can be controlled according to different strains, the usage mode is flexible and changeable, the modification of the existing device is small, it can significantly shorten the incubation period of the strain, improve the efficiency of clinical detection and diagnosis, and the economic benefit is significant;

[0047] (3) The present invention has an infrared sensor patch in the unit cavity. Based on the real-time detection of two parameters, the carbon dioxide concentration P and the rate of change of carbon dioxide concentration V in the blood culture bottle, the magnetic field strength is adjusted according to the different growth stages of bacteria to match the rotation speed of different magnetic rotors. This can further optimize dissolved oxygen, improve bacterial culture effect and culture rate, and save energy.

[0048] (4) The present invention is equipped with a heating component in each unit cavity and a temperature control component at the bottom of the unit cavity, which can ensure that the blood culture bottles in each unit cavity are incubated at a constant temperature and are not affected by the airflow when the box is opened and closed, thereby further improving the incubation effect; at the same time, for blood culture bottles with magnetic rotors inside and placed in unit cavities within a controllable magnetic field, the magnetic field controls the rotation of the magnetic rotors to generate some heat, which can offset some of the heating required by the heating component, achieving energy complementarity and full utilization. Moreover, the rotation of the magnetic rotors promotes gas flow, which is also beneficial to the constant temperature control effect and the quality of constant temperature incubation.

[0049] (5) The infrared sensor patch and temperature sensor patch of the present invention are both set in the opening groove of the heating component, which can prevent the heating component from directly contacting the infrared sensor patch and temperature sensor patch, thus affecting the detection sensitivity and sensor lifespan.

[0050] (6) An auxiliary cavity is provided on the inner wall of the unit cavity corresponding to the opening slot of the side heating component of the present invention. The bottom of the auxiliary cavity is located above the infrared sensor patch and the temperature sensor patch. The outer side wall of the elastic insert inserted into the auxiliary cavity protrudes from the inner side wall of the side heating component. When the blood culture bottle is inserted into the unit cavity, the outer side wall of the elastic insert is squeezed and deformed by the blood culture bottle, which can easily and conveniently fix the blood culture bottle in the unit cavity automatically. It is convenient to use and has a simple and compact structure. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the structure of the cultivation detection seat according to an embodiment of the present invention;

[0052] Figure 2 This is a schematic diagram of the arrangement of the internal unit cavity and electromagnet of the cultivation detection seat according to an embodiment of the present invention. Figure 1 ;

[0053] Figure 3 This is a schematic diagram of the structure of the cultivation detection seat of the present invention, which is equipped with an electromagnet and a magnetic shielding plate. Figure 1 ;

[0054] Figure 4 This is a schematic diagram of the structure of the cultivation detection seat of the present invention, which is equipped with an electromagnet and a magnetic shielding plate. Figure 2 ;

[0055] Figure 5 This is a schematic diagram of the planar structure of the unit cavity according to an embodiment of the present invention;

[0056] Figure 6 This is a schematic diagram of the structure of the elastic insert according to an embodiment of the present invention;

[0057] Figure 7 This is a perspective view of the unit cavity containing the elastic insert in an embodiment of the present invention;

[0058] Figure 8 This is a cross-sectional view of the unit cavity containing the elastic insert in an embodiment of the present invention;

[0059] Figure 9 This is a schematic diagram of the structure of a blood culture bottle with a magnetic rotor during shaking incubation according to an embodiment of the present invention.

[0060] The markings in the diagram are as follows: 1-Cultivation and detection seat; 2-Unit cavity; 3-Electromagnet; 4-Magnetic shielding plate; 5-Auxiliary cavity; 6-Side heating assembly; 7-Elastic insert; 8-Infrared sensor patch; 9-Temperature sensor patch; 10-Bottom heating assembly; 11-Temperature control cavity; 12-Blood culture bottle; 13-Magnetic rotor. Detailed Implementation

[0061] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0062] In the description of this invention, it should be understood that the terms "coaxial," "bottom," "one end," "top," "middle," "other end," "upper," "side," "top," "inner," "front," "center," "both ends," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0063] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," "fixing," "screw connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components or the interaction between two components. Unless otherwise explicitly limited, those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0064] Combination Figure 1-6 As shown, this embodiment provides a blood culture mixing method and apparatus with a rotor. The core of this mixing method lies in using a blood culture bottle with a rotor to achieve mixing. By controlling the magnetic rotor for mixing, the existing inverted mixing and continuous rotation mixing methods are replaced. This not only effectively improves the mixing effect but also protects the mixing structure or apparatus, extending its service life. Furthermore, the "rotation-stationary alternation" mode and coordinated control with detection resolve the contradiction of continuous rotation interfering with detection. Moreover, the "mixing-detection" dual function is optimized through time segmentation. No new hardware is required; only the control algorithm needs to be modified. This method is suitable for upgrading existing blood culture instruments and is cost-effective.

[0065] Specifically, the present invention provides a mixing device for a blood culture bottle with a rotor, which includes a box, a blood culture bottle 12 with a magnetic rotor, and a culture detection seat 1. The box is provided with a plurality of culture detection seats 1, and the culture detection seats 1 are provided with a plurality of unit cavities 2. Each unit cavity 2 can hold a blood culture bottle 12 with a magnetic rotor.

[0066] like Figure 2 As shown, an electromagnet 3 is installed in the culture detection seat 1. The electromagnet 3 is a three-phase AC coil electromagnet. A blood culture bottle 12 is placed inside the unit cavity 2. A magnetic rotor 13 is installed inside the blood culture bottle 12. The magnetic rotor 13 is spherical and can be made of silicon steel or Fe3O4. The magnetic field generated by the electromagnet 3 when energized will drive the magnetic rotor 13 to rotate at high speed (see...). Figure 9 This causes the culture medium inside the blood culture bottle 12 to rotate, forming a vortex. This allows the oxygen in the blood culture bottle 12 to fully mix with the culture medium, increasing dissolved oxygen levels, promoting bacterial culture, shortening the incubation period, and significantly improving the efficiency of clinical testing and diagnosis.

[0067] Specifically, as one embodiment, the cultivation detection seat 1 may be provided with a plurality of longitudinally or laterally arranged unit cavities 2, and an electromagnet 3 is installed near each unit cavity 2. The shape of the electromagnet 3 is selected according to the situation and is not limited here. Each electromagnet 3 and the magnetic rotor 13 in each unit cavity 2 constitute a set of integrated structures that generate eddy currents. An isolation structure is provided between each set of integrated structures, such as an isolation plate, an isolation frame, or a magnetic shield. The isolation structure can ensure that the magnetic fields between each set of integrated structures do not interfere with each other, and further ensure that each The magnetic rotor in the integrated structure can rotate stably to form eddy currents. Furthermore, in order to better control the magnetic field generated by the electromagnet to facilitate the generation of stable eddy currents in the magnetic rotor 13, each electromagnet 3 can be connected to an integrated control module. It should be noted that the electromagnet 3 is equivalent to a "super magnet" that can be switched on and off, its intensity adjusted, and its direction changed as needed, while the magnetic rotor 13 is equivalent to a "magnet" or "conductor" that can rotate freely. By precisely controlling the magnetic field of the electromagnet 3, it is possible to more accurately drive the magnetic rotor 13 to rotate, generate current, or control its motion state.

[0068] Specifically, the integrated control module includes, but is not limited to, switches for basic on / off control, such as mechanical switches (e.g., push-button switches, toggle switches, rotary switches, relays, etc.). The control principle of the mechanical switch is: to manually or through other means (e.g., energizing the relay coil) close or open the circuit, thereby connecting or disconnecting the current flowing through the coil. It should be noted that this structure is a conventional structure and the principle is well-known, so it will not be elaborated further.

[0069] Furthermore, the integrated control module can also include components for current regulation, such as adjustable linear power supplies and switching power supplies (with voltage regulation function). Their control principle is: directly adjusting the output voltage of the power supply, according to Ohm's law (I=U / R), with the electromagnet coil resistance R remaining essentially constant, adjusting the voltage U linearly regulates the current. Other examples include power operational amplifiers and linear voltage regulator integrated circuits (such as LM317 with power transistor current amplification). Their working principle is: inputting a control signal (such as analog voltage from a microcontroller or DAC output) to a linear amplifier circuit, which operates in the linear region, and its output voltage or current changes linearly with the input signal, driving the electromagnet coil. It should be noted that these structures are all conventional, and their principles are well-known, so they will not be elaborated upon further.

[0070] Furthermore, the integrated control module can also include a bridge circuit composed of four switching transistors (usually MOSFETs or IGBTs). Its principle is as follows: Controlling the switching transistors on the opposite diagonal simultaneously (e.g., switching transistors Q1 and Q4 are on, while switching transistors Q2 and Q3 are off), the current flows from the positive terminal of the power supply through Q1 to the coil, then to Q4, and back to the negative terminal of the power supply. The current direction in the coil is from one position (e.g., A) to another position (e.g., B). Controlling the switching transistors on the other diagonal simultaneously (e.g., Q2 and Q3 are on, while Q1 and Q4 are off), the current flows from the positive terminal of the power supply through Q2 to the coil, then to Q3, and back to the negative terminal of the power supply. The current direction in the coil is from B to A. By controlling different combinations of switching transistors, bidirectional current flow (forward, reverse, braking, rapid stop) can be achieved. Its key feature is that the core circuit for reversing the current direction is usually combined with PWM control, which can not only control the direction but also precisely control the magnitude of the current in that direction. It should be noted that these structures are all conventional structures, and the principles are well-known, so they will not be elaborated on further.

[0071] It should be further noted that this integrated control module can also be configured to generate PWM signals based on a microcontroller / DSP / PLC to drive MOSFETs / IGBTs (typically forming an H-bridge). This is the most flexible, efficient, precise, and cost-effective preferred method for controlling the current of an electromagnet coil. The integrated motor driver module significantly simplifies the implementation of small to medium power applications. In the fields of industrial automation and high precision, PLCs and dedicated motion controllers provide a powerful platform and performance guarantee.

[0072] In this embodiment, the control principle and control structure of the integrated control module are conventional methods, which will not be elaborated on here. It should be noted that the integrated control module can control the magnitude and direction of the current, which can ensure that the magnetic rotor can rotate stably in the blood culture bottle 12.

[0073] like Figure 2 The diagram shows a longitudinal arrangement. A predetermined distance d is set between each pair of integrated structures. This distance d ensures that the magnetic fields of adjacent electromagnets 3 do not interfere with each other. The specific distance d is determined experimentally based on the required maximum magnetic field strength. In this way, the magnetic field strength between each group can be controlled independently, making the control more efficient and flexible. The farther the unit cavity without electromagnets is from the electromagnets, the weaker the magnetic field strength. This is used to place blood culture bottles 12 with magnetic rotors 13 whose required magnetic field strength gradually decreases (i.e., the dissolved oxygen demand gradually decreases), thus making full use of the structural space of the device and ensuring a compact size.

[0074] As another embodiment, refer to Figure 3As shown, the isolation structure between each pair of integrated structures is a magnetic shielding plate 4. The magnetic shielding plate 4 is a thin iron plate with a thickness of no more than 4mm. The magnetic shielding plate 4 can isolate the magnetic field and ensure that the magnetic fields of adjacent electromagnets 3 do not interfere with each other. This allows the magnetic field strength of each unit cavity 2 to be controlled independently, making the control more precise while making the structure of the entire device more compact.

[0075] As another embodiment, refer to Figure 4 As shown, each unit cavity 2 is provided with an electromagnet 3 at the bottom or side. Magnetic shielding plates 4 are provided between two adjacent unit cavities 2, both vertically and horizontally, so that the magnetic shielding plates 4 are arranged in a grid pattern, which isolates the magnetic field of each unit cavity 2. The magnetic field strength of each unit cavity 2 is independently controlled, enabling more precise culture for each blood culture bottle.

[0076] As a further improvement, an infrared sensor patch 8 is provided inside the unit cavity 2 (see...). Figure 7 The infrared sensor patch 8 can be disposed on the bottom or side wall of the unit cavity 2, and is used to detect and analyze changes in carbon dioxide content in the blood culture bottle 12 through infrared spectroscopy, and adjust the magnetic field strength of the electromagnet 3 accordingly, thereby controlling the rotation speed of the magnetic rotor 13. The specific control process is as follows:

[0077] The infrared sensor patch 8 monitors the carbon dioxide concentration P and the rate of change V of carbon dioxide concentration in the blood culture bottle 12 in real time, and compares the carbon dioxide concentration P and the rate of change V of carbon dioxide concentration with set thresholds respectively:

[0078] If the carbon dioxide concentration P < concentration threshold P0 and the rate of change of carbon dioxide concentration V < rate threshold V0, it means that the current carbon dioxide concentration is low and the rate of change of carbon dioxide concentration is small, and the bacteria are in a slow growth stagnation period. Then the magnitude of the control current I is: first current threshold I1 < current I < second current threshold I2, and thus the magnitude of the control magnetic field strength H is: first magnetic field strength H1 < magnetic field strength H < second magnetic field strength H2.

[0079] If the carbon dioxide concentration P < the concentration threshold P0, and the rate of change of carbon dioxide concentration V > the rate threshold V0, it means that the current carbon dioxide concentration is low, but the rate of change of carbon dioxide concentration is large, and the bacteria are in the rapid growth logarithmic phase. In this case, the control current I > the second current threshold I2, thereby controlling the magnetic field strength H > the second magnetic field strength H2.

[0080] If the carbon dioxide concentration P > the concentration threshold P0 and the rate of change of carbon dioxide concentration V < the rate threshold V0, it means that the current carbon dioxide concentration is high and the rate of change of carbon dioxide concentration is small, and the bacteria are in a stable plateau phase of growth. In this case, the control current I < the first current threshold I1. If necessary, the electromagnet 3 can be de-energized to control the magnetic field strength H < the first magnetic field strength H1, or to prevent the generation of a magnetic field.

[0081] The above-mentioned method comprehensively judges the carbon dioxide concentration P and the rate of change of carbon dioxide concentration V in the blood culture bottle, and provides varying magnetic field strength according to different growth stages of bacteria to match the rotation speed of different magnetic rotors. This can further optimize the dissolved oxygen of the culture medium, improve the bacterial culture effect and culture rate, and save energy.

[0082] Furthermore, in conjunction with the aforementioned scheme and the core principle of electromagnetic speed regulation, the magnetic field strength generated by electromagnet 3 can be precisely controlled by changing the magnitude of the current in the electromagnet coil. Moreover, the direction of the magnetic field generated by electromagnet 3 can be precisely controlled by changing the direction of the current in the electromagnet coil, thereby changing the rotational speed of the magnetic rotor 13 (or the rotor containing magnetic components) that interacts with it.

[0083] In addition, see Figure 7 As shown, the unit cavity 2 in this embodiment of the invention is also provided with a heating component and a temperature sensor 9. The heating component includes a side heating component 6 surrounding the inner wall of the unit cavity 2 and a bottom heating component 10 disposed at the bottom of the unit cavity 2. The side heating component 6 has two opening slots. An infrared sensor patch 8 for detecting changes in carbon dioxide content in the blood culture bottle 12 is disposed on the inner wall of the unit cavity 2 corresponding to one of the opening slots. A temperature sensor patch 9 for real-time temperature detection is disposed on the inner wall of the unit cavity 2 corresponding to the other opening slot.

[0084] A temperature control cavity 11 is provided at the bottom of the unit cavity 2 (see Figure 8-9 The temperature control chamber 11 contains a temperature control component. The temperature control component is used to adjust the heating temperature of the heating component in real time according to the temperature of the blood culture bottle 12 detected in real time by the temperature sensor patch 9, so that the blood culture bottle 12 maintains a constant incubation temperature and the incubation temperature is not affected by the airflow when the bottle is loaded and unloaded.

[0085] For a blood culture bottle 12 with a magnetic rotor 13 inside, placed in a unit cavity within a controllable magnetic field, the magnetic field controls the rotation of the magnetic rotor 13, which can also generate some heat. This heat can offset some of the heating required by the heating components, achieving energy complementarity and full utilization. Furthermore, the rotation of the magnetic rotor 13 promotes gas flow, which is also beneficial to the constant temperature control effect and the quality of constant temperature incubation.

[0086] Meanwhile, the infrared sensor patch 8 and the temperature sensor patch 9 are both set in the opening slot of the heating component, which can prevent the heating component from directly contacting the infrared sensor patch 8 and the temperature sensor patch 9, thus avoiding affecting the sensitivity of the sensor during detection and the service life of the sensor.

[0087] Furthermore, an auxiliary cavity 5 is provided on the inner wall of the unit cavity 2 corresponding to the opening slot of the side heating assembly 6. The bottom of the auxiliary cavity 5 is located at the upper end of the infrared sensor patch 8 / temperature sensor patch 9 (see...). Figure 7 An elastic insert 7 is inserted into the auxiliary cavity 5. The elastic insert 7 is a cylindrical rubber rod or a hollow rubber tube. The outer side wall of the elastic insert 7 protrudes from the inner side wall of the side heating component 6. When the blood culture bottle 12 is inserted into the unit cavity, the outer side wall of the elastic insert 7 is squeezed and deformed by the blood culture bottle 12, which can easily and conveniently fix the blood culture bottle 12 in the unit cavity 2 automatically, making it convenient to use.

[0088] In this embodiment, the mixing device is also electrically or communicatively connected to a control terminal. The control terminal can be a computer or other terminal device, which can be used to monitor data during the mixing process in real time and to input, output or set parameters.

[0089] In some other embodiments, the specific steps of the mixing method include:

[0090] Step 1: Assemble the mixing device and set the initialization parameters;

[0091] In this embodiment, the initialization parameters mainly include the following parts:

[0092] (1) Set the duration of the mixed period T1 (e.g., 3 minutes by default) and the duration of the static period T2 (e.g., 1 minute by default);

[0093] (2) Set the active damping current parameters of electromagnet 3: reverse pulse width t≤10ms, pulse amplitude I=1.5×working current;

[0094] (3) Configure the sensor trigger delay time t d = 0.5 seconds;

[0095] (4) Base speed setting:

[0096] Retention period: ω_base = 500 RPM;

[0097] Logarithmic period: ω_base = 1000 RPM;

[0098] Plateau period: ω_base = 600 RPM;

[0099] It should be noted that in microbial culture (especially blood culture), the retention phase, logarithmic phase, and plateau phase are three typical stages of bacterial growth, reflecting the complete process of microorganisms from adapting to the environment to rapid proliferation and then to equilibrium; these will not be discussed in detail here.

[0100] Step 2: Start the electromagnet 3 to drive the magnetic rotor 13 to rotate and monitor the liquid condition during the mixing cycle;

[0101] In this embodiment, the first stage is the mixed period (T1 stage), and the specific process is as follows:

[0102] a) When three-phase alternating current is applied to the electromagnet, the current I = I_max (e.g., 5A) drives the rotor to rotate at a high speed of 1200RPM.

[0103] b) Monitor rotor speed in real time (by sampling back electromotive force) and maintain speed fluctuation ≤ ±5%;

[0104] c) Record the end time t1 of the mixing period;

[0105] The second stage is the quiescent period (T2 stage), and the specific process is as follows:

[0106] d) Cut off the main current of the electromagnet at time t1;

[0107] e) Immediately apply a reverse damping pulse (reverse current I, duration t, the specific duration is determined based on experience);

[0108] f) After a set delay time t_d, the infrared sensor is activated to detect the CO2 concentration P and the rate of change V;

[0109] g) Synchronously acquire turbidity data (optical sensor) and temperature data (temperature sensor patch 9);

[0110] In some other embodiments, during the quiescent period, impedance analysis can also be used to monitor the liquid viscosity. The monitoring process is as follows:

[0111] 1) A 10kHz high-frequency detection signal (amplitude 0.1A) is superimposed on the electromagnet's operating current;

[0112] 2) Calculate the viscosity η = K·Δφ (K is the calibration coefficient) based on the phase difference Δφ of the sampling coil voltage (the phase difference before and after superimposing the detection signal);

[0113] 3) If η > 15 mPa·s, the viscosity compensation mechanism is triggered;

[0114] Specifically, the viscosity compensation mechanism is as follows:

[0115] If η > 15 mPa·s: ω_adj = ω_base × (1 + 0.3 × (η - 15) / 10); where ω_adj is the actual output speed after viscosity compensation, in RPM (revolutions per minute); it should be noted that ω_base is the data corresponding to the typical stage.

[0116] Specifically, viscosity compensation involves two motion modes, including continuous rotation mode and swing mode.

[0117] Among them, continuous rotation mode (η ≤ 25 mPa·s):

[0118] A) Calculate the PWM duty cycle D = ω_adj / ω_max × 100%;

[0119] B) Output three-phase PWM current by the H-bridge to drive the rotor to rotate unidirectionally.

[0120] Swing mode (η > 25 mPa·s):​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0131] Step 4: Repeat steps 2-3 until the culture is complete (total time T_total = 24-48 hours). It should be noted that the conditions for ending the culture are based on achieving the required mixing standard according to actual conditions, and are set empirically, so they will not be detailed further.

[0132] The above description is merely an embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A method of mixing a blood culture bottle with a rotor, characterized by, The method comprises the following steps: Step 1, assemble the mixing device and set the initial parameters; Step 2, start the electromagnet to drive the magnetic rotor to rotate, and monitor the liquid during the mixing period; Step 3: According to the monitoring situation, make data decision and parameter adjustment; Step 4: Loop until the end of the culture.

2. A method of mixing a blood culture bottle with a rotor as defined in claim 1, wherein, In step 1, setting the initial parameters includes: (1) Set the mixing period T1 and the static period T2; (2) Set the active damping current parameters of the electromagnet: the reverse pulse width t≤10ms, the pulse amplitude I=1.5×working current; (3) Configure sensor trigger delay time t d = 0.5 seconds; (4) Basic speed setting: Stationary phase: ω_base=500RPM; Logarithmic phase: ω_base=1000RPM; Plateau phase: ω_base=600RPM.

3. A method of mixing a blood culture bottle with a rotor as defined in claim 2, wherein, In step 2, the mixing period includes a first stage; and the first stage is the mixing period, and the monitoring process is: a) The electromagnet is connected to three-phase alternating current, the current I=I_max, and the magnetic rotor is driven to rotate at a high speed of 1200RPM; b) Real-time monitoring of rotor speed, maintaining speed fluctuation≤±5%; c) Record the end time t1 of the mixing period.

4. A method of mixing a blood culture bottle with a rotor as defined in claim 3, wherein, In step 2, the mixing period also includes a second stage; and the second stage is the static period, and the monitoring process is: d) Cut off the main current of the electromagnet at t1; e) And immediately apply a reverse damping pulse; f) After a delay set time, start the infrared sensor to detect CO2 concentration P and change rate V; g) Synchronously collect turbidity data and temperature data.

5. A method of mixing a blood culture bottle with a rotor as defined in claim 4, wherein, In the static period, impedance analysis method is also used to monitor the viscosity of the liquid, and the monitoring process is: 1) Superimpose a 10kHz high-frequency detection signal on the electromagnet working current; 2) Sample coil voltage phase difference Δφ, calculate viscosity η=K·Δφ, where K is the calibration coefficient; 3) If η>15mPa·s, trigger the viscosity compensation mechanism.

6. A method of mixing a blood culture bottle with a rotor as defined in claim 5, wherein, The viscosity compensation mechanism is: If η>15mPa·s, ω_adj=ω_base×(1+0.3×(η-15) / 10); Where ω_adj is the actual output speed after viscosity compensation, unit: RPM.

7. A method of mixing a blood culture bottle with a rotor as defined in claim 6, wherein, The viscosity compensation mode includes continuous rotation mode, In continuous rotation mode, η≤25mPa·s: A) Calculate PWM duty cycle D=ω_adj / ω_max×100% according to ω_adj; B) Output three-phase PWM current from H bridge to drive the rotor to rotate in one direction.

8. A method of mixing a blood culture bottle with a rotor as defined in claim 7, wherein, The viscosity compensation mode also includes swing mode, In swing mode, η>25mPa·s: C) Control the electromagnet rotor to reciprocate within ±30°; D) Swing frequency f=2Hz; E) Current waveform: triangular wave.

9. The method of claim 2, wherein the mixing is performed by rotating the blood culture bottle. In step 3, the process is: Step 31, update the next cycle parameters according to the monitoring results: When it is stationary phase, if CO2 concentration P<threshold value P0 and V<V0: set the mixing period current I=0.6I_max and the speed to 600RPM in the next cycle; Where V0 is the initial rate; When it is logarithmic phase, if CO2 concentration P<threshold value P0 and V>V0: set the mixing period current I=I_max and the speed to 1200RPM in the next cycle; When the platform period, if the CO2 concentration P> threshold P0 and V < V0: set the next period mixed current I = 0.3I_max, 400 RPM speed; Step 32, according to the turbidity data compensation detection interference: if the turbidity fluctuation > threshold ΔNTU, then extend the static period T2'=T2+30 seconds.

10. A mixing device for a blood culture bottle with a rotor, characterized in that The mixing method of the blood culture bottle with the rotor according to any one of claims 1-9 is executed; the mixing device comprises a box body, a blood culture bottle with a magnetic rotor and a culture detection seat, a plurality of culture detection seats are arranged in the box body, a plurality of unit cavities are arranged on the culture detection seat, and the blood culture bottle is placed in the unit cavity; at least one magnetic rotor is arranged in the blood culture bottle; a magnetic field generating device is arranged outside the blood culture bottle, and the magnetic field generated by the magnetic field generating device drives the magnetic rotor to rotate in the blood culture bottle, thereby driving the culture solution in the blood culture bottle to rotate to form a vortex, and increasing the oxygen solubility of the culture solution.

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