Medical vehicle-mounted constant-temperature preservation box electrical system and control method thereof

Abstract

The application relates to the technical field of medical equipment and electrical control, in particular to a medical vehicle-mounted constant-temperature storage box electrical system and a control method thereof, the system comprises a dual-power supply module, a DC-DC voltage stabilizing module, a temperature control unit, an anti-inclination sensor and a control module, the dual-power supply module realizes seamless switching between commercial power and a 24V 60Ah lithium battery pack, and cooperates with the voltage stabilizing module to guarantee stable power supply; the control method accurately controls refrigeration and heating units according to the heating wire activation state through a segmented algorithm combined with a preset working point temperature St, a control temperature difference rd1 and rd2; the anti-inclination protection adopts double-angle threshold values and a delay logic, the compressor is stopped when the inclination theta is greater than or equal to AA1, the compressor is restarted after a delay of 3 minutes when the inclination theta is less than AA2, and an E60 alarm is triggered when communication is abnormal. The application realizes high-precision temperature control, is suitable for multiple transfer scenes, improves the safety of medical material transfer and the reliability of equipment, and has wide popularization value.

Description

Technical Field

[0001] This invention relates to the field of medical equipment and electrical control technology, specifically to an electrical system and control method for a vehicle-mounted constant temperature preservation box for medical use. Background Technology

[0002] In the field of medical transport, supplies such as blood, vaccines, biological samples, and special drugs have extremely high requirements for the stability of storage temperature and the safety of transportation. Excessive temperature fluctuations or equipment failures during transportation can easily lead to the deterioration or ineffectiveness of medical supplies, thereby affecting clinical treatment outcomes and even posing medical safety risks. As a core piece of equipment in medical transport, vehicle-mounted temperature-controlled storage boxes must be adapted to the complex operating conditions of mobile vehicle scenarios, balancing power supply stability, temperature control accuracy, and operational safety. The performance of its electrical system directly determines the quality of medical supply transport.

[0003] Current medical vehicle-mounted thermostatic storage boxes have numerous technical shortcomings in their electrical systems, making it difficult to meet the stringent requirements of clinical transport. Regarding power supply, most devices employ a single power source, either relying solely on AC mains power, which is unsuitable for long-distance transport scenarios without AC mains power, or being equipped only with lithium batteries. These batteries have limited range and lack reliable power monitoring and charging protection mechanisms, making them prone to shutdown due to battery depletion. While some dual-power devices offer AC mains and lithium battery switching, the switching logic is cumbersome and lacks a stable voltage regulator module. Voltage fluctuations on the vehicle can easily damage the downstream precision temperature control circuitry, affecting the stability of the equipment's operation.

[0004] In terms of temperature control performance, existing equipment mostly adopts a single cooling or heating control mode with simple temperature control algorithms. This results in a lack of flexibility in adjusting control strategies based on changes in ambient temperature, leading to problems such as excessively low temperatures in low-temperature environments and excessive temperature fluctuations in high-temperature environments. It is difficult to accurately maintain the internal temperature within the preset range. Furthermore, some equipment lacks coordinated control logic between the cooling and heating units, resulting in inaccurate start-up and shutdown timing. This not only leads to poor temperature control accuracy but also increases energy consumption and shortens lithium battery life.

[0005] In terms of safety protection, the anti-tilt protection function of existing vehicle-mounted constant temperature storage boxes is inadequate. Most only have a single tilt threshold, and the compressor restarts immediately after the tilt angle is restored. This can easily lead to frequent compressor starts and stops due to vehicle bumps, causing component wear and shortening the equipment's lifespan. Furthermore, some devices lack an effective communication fault alarm mechanism. When the temperature control module and tilt detection module experience communication abnormalities, they cannot promptly alert operators to troubleshoot the fault, potentially leading to temperature control malfunction or equipment damage. In addition, the operating logic of existing equipment is complex, and the control of power switching and heating function start / stop lacks a clear linkage mechanism, making it prone to power outages or temperature control malfunctions due to misoperation.

[0006] In view of the shortcomings of the existing technologies, there is an urgent need for an electrical system and control method for a medical vehicle-mounted constant temperature storage box that is adapted to complex vehicle-mounted operating conditions, has stable power supply, precise temperature control, and comprehensive safety protection. This would solve the problems of existing equipment in terms of power supply reliability, temperature control accuracy, safety protection, and ease of operation, and ensure the safety and stability of medical supplies transportation throughout the entire process. Summary of the Invention

[0007] The purpose of this invention is to provide an electrical system and control method for a medical vehicle-mounted constant temperature preservation box, so as to solve the problems mentioned in the background art regarding the reliability of power supply, temperature control accuracy, safety protection and ease of operation of existing equipment.

[0008] To achieve the above objectives, the present invention provides the following technical solution: An electrical system for a vehicle-mounted constant temperature storage box for medical use includes a dual power supply module, a DC-DC voltage regulator module, a power display unit, a battery switch, a power switch, a cooling unit, a heating unit, a temperature sensor, an anti-tilt sensor, an electronic temperature controller, and a control module. The dual power supply module includes a 220VAC AC mains power supply branch and a lithium battery pack power supply branch. The AC mains power supply branch is connected to the system via a 24V 14A switching power supply, and the lithium battery pack power supply branch is connected to a charging power supply via a 10A charger. The DC-DC voltage regulator module is connected to the dual power supply module and the subsequent circuit, respectively, and is used to stably output the input power to DC24V; the power display unit is connected to the lithium battery pack and is used to monitor the power of the lithium battery pack in real time. The battery life switch and power switch are linked with the dual power supply module to achieve power supply mode switching; the temperature sensor and anti-tilt sensor are respectively connected to the electronic temperature controller and the control module; the electronic temperature controller is respectively connected to the cooling unit and the heating unit; the control module is linked with the dual power supply module, the anti-tilt sensor and the electronic temperature controller to achieve anti-tilt protection control and power supply logic control. The refrigeration unit includes a refrigerated DC compressor, a condenser fan, and an evaporator fan. The heating unit includes a heating wire. The electronic temperature controller achieves precise start-stop control of the refrigeration unit and the heating unit through a control algorithm.

[0009] Preferably, the lithium battery pack has a specification of 24V 60Ah, the 24V 14A switching power supply of the mains power supply branch is used to convert 220VAC to 24VDC, and the 10A charger has an input voltage of 220VAC and an output voltage of 24VDC, and is used to charge the lithium battery pack.

[0010] Preferably, the control logic for the battery life switch and the power switch is as follows: When switching to transport mode, disconnect the power switch and close the end-of-life switch; the system will then switch to lithium battery power. When the mains power supply is used or the customer's lithium battery pack is used to generate 220VAC power, close the power switch and disconnect the end-of-life switch to switch the system to the mains power supply branch. When not using the device at night or for an extended period of time, simultaneously disconnect the battery life switch and the power switch. During the charging process of the lithium battery pack, the battery life switch remains off.

[0011] Preferably, the heating wire is equipped with a parameter switch, which is on by default and can be manually turned off or on by means of the parameter switch.

[0012] Preferably, the output voltage of the DC-DC voltage regulator module is constant at DC24V, which is used to provide stable power supply to downstream circuits such as the refrigeration DC compressor drive board, condenser fan, evaporator fan, and electronic temperature controller, so as to avoid damage to downstream circuits caused by voltage fluctuations.

[0013] On the other hand, the present invention also provides a control method based on the above-mentioned electrical system of the medical vehicle-mounted constant temperature storage box, comprising the following steps: (1) Dual power supply switching control: When the transfer point is connected to the mains power 220VAC, the system is powered through the mains power supply branch; during the transfer, the power supply is switched to the lithium battery pack power supply branch, and the system is powered through the lithium battery pack. (2) Power monitoring and charging control: The power information of the lithium battery pack is collected in real time through the power display unit. When the power is insufficient, the power of the lithium battery pack is replenished by a 10A charger at the transfer point. During the charging process, the end-of-life switch is disconnected. (3) Precise control of cooling and heating: The electronic temperature controller controls the start and stop of the cooling unit and the heating unit by means of the real-time temperature collected by the temperature sensor, combined with the preset working point temperature St, the control temperature difference rd1 and rd2, and the control algorithm. (4) Anti-tilt protection control: The control module collects the tilt angle of the storage box in real time through the anti-tilt sensor. When the tilt angle meets the preset threshold condition, the compressor of the refrigeration unit is controlled to start and stop. When the temperature controller communicates abnormally with the tilting module, an alarm is triggered.

[0014] Preferably, in step (3), when the heating wire is not activated, the control algorithm for the refrigeration unit is as follows: When real-time temperature At this time, the electronic thermostat sends a switch-off signal to control the compressor to stop working; When real-time temperature At that time, the electronic temperature controller sends a switch closure signal to control the compressor to start working; in, To preset the operating point temperature, , The temperature difference is preset to control the temperature difference.

[0015] Preferably, in step (3), when the heating wire is activated, the control algorithms for the cooling unit and the heating unit are as follows: Cooling control: when the real-time temperature When the electronic thermostat sends a switch-off signal, it controls the compressor to stop working; when the real-time temperature... At that time, the electronic temperature controller sends a switch closure signal to control the compressor to start working; Heating control: When the real-time temperature When the electronic temperature controller closes the power supply to the heating wire, it controls the heating wire to start heating; when the real-time temperature... When this happens, the electronic temperature controller disconnects the power supply to the heating wire, stopping the heating wire from heating. in, To preset the operating point temperature, , The temperature difference is preset to control the temperature difference.

[0016] Preferably, when the anti-tilt sensor detects the tilt angle of the storage box... When this happens, the control module sends a stop signal to stop the compressor from working; When the anti-tilt sensor detects the tilt angle of the storage box When the delay occurs, the control module initiates a delay program, and after a 3-minute delay, sends a recovery signal to control the compressor to resume operation. When a communication failure occurs between the temperature controller and the tilting module, the control module triggers an E60 alarm signal; in, The tilt angle threshold at which the compressor stops. The tilt angle threshold for resuming compressor operation, and .

[0017] Preferably, in step (2), the full charge voltage of the lithium battery pack is 29.3V±0.2V. The power display unit provides real-time feedback on the remaining power of the lithium battery pack through the power display progress module. When the remaining power is lower than the preset threshold, a charging prompt signal is issued to remind the user to replenish the power of the lithium battery pack at the transfer point.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention effectively solves the core pain points of unstable power supply and insufficient battery life in vehicle-mounted transportation scenarios through a dual-power supply module and linkage control logic design, significantly improving the adaptability and reliability of the equipment. The dual-power supply branch can achieve seamless switching between AC mains power and lithium battery pack. AC mains power supply meets the needs of fixed transportation points. The combination of a 24V 14A switching power supply and a 10A charger ensures power conversion efficiency and lithium battery pack charging safety. The 24V 60Ah lithium battery pack, with real-time power monitoring and early warning functions, can support long-term continuous transportation on a single full charge. The dual-battery alternating power supply scheme is more suitable for cross-regional and long-distance needs. At the same time, the DC-DC voltage regulator module continuously outputs a stable 24VDC voltage, avoiding damage to downstream temperature control, sensing and other precision circuits caused by voltage fluctuations, ensuring continuous and stable operation of the equipment in complex vehicle-mounted environments.

[0019] 2. This invention achieves high-precision temperature control within the enclosure through a segmented temperature control algorithm and a collaborative control strategy, meeting the stringent temperature requirements for medical samples and pharmaceuticals. The electronic temperature controller switches the corresponding control logic based on the heating wire's activation status. By using preset operating point temperature and temperature difference parameters, it precisely controls the start and stop timing of the cooling and heating units. The heating wire is on by default and supports manual switching, flexibly adapting to different ambient temperature scenarios. Compared to traditional single temperature control modes, this invention, through bidirectional collaborative control of cooling and heating, keeps temperature fluctuations within a smaller range. Combined with real-time feedback from a high-precision temperature sensor, it ensures that the temperature inside the enclosure remains stable within the preset range, effectively preventing the deterioration or failure of medical supplies due to temperature fluctuations and improving the safety of supplies during transportation.

[0020] 3. This invention integrates multiple safety protection mechanisms and a user-friendly control design, balancing equipment operation safety and ease of use, and possesses strong practical value. The anti-tilt sensor and control module work together to form a closed-loop protection system. Through preset dual-angle thresholds and delayed recovery logic, compressor failure under tilt conditions is prevented. The E60 alarm signal triggered in case of communication abnormalities can promptly alert operators to troubleshoot the problem. The clear linkage logic between the endurance switch and the power switch reduces the risk of power outages or equipment damage due to misoperation. The design of the heating wire parameter switch and power display unit enhances the ease of operation. The overall system structure is compact, and the control logic is clear. It is suitable for various transport scenarios, including short-distance urban transport, low-temperature environments, and long-distance cross-regional transport, while ensuring the safety and stability of medical supply transport throughout the entire process, and has broad application prospects. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are explained in detail together with the embodiments of the invention, but do not constitute a limitation thereof.

[0022] Figure 1This is a diagram showing the system module connection architecture of the present invention; Figure 2 This is a modular composition diagram of the dual-power electrical system of the present invention; Figure 3 This is a flowchart illustrating the dual-power electrical system control method of the present invention. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] (I) System Overall Structure and Working Principle like Figure 1 and Figure 2 As shown, the core of the electrical system of the medical vehicle-mounted constant temperature preservation box of this invention lies in achieving stable power supply, precise temperature control, and safety protection in vehicle-mounted scenarios, adapting to scenarios with extremely high requirements for temperature stability and transportation safety, such as medical samples and medicines. The system uses a dual power supply module as its energy core, a DC-DC voltage regulator module to ensure the power supply stability of the downstream circuits, and an electronic temperature controller and control module to work together to realize temperature control logic and safety protection. The linkage of each unit forms a closed-loop control to ensure that the temperature inside the preservation box is maintained within the preset range, while also coping with complex conditions such as tilting and power supply switching during vehicle transportation.

[0025] The dual power supply module adopts a dual-path design of AC power and lithium battery pack, taking into account both fixed power supply at the transfer point and mobile power supply needs during transit. When powered by AC power, 220VAC is converted to 24VDC through a 24V 14A switching power supply, and then processed by a DC-DC voltage regulator module to power the subsequent circuits. The lithium battery pack adopts a 24V 60Ah specification, with a full-charge voltage of 29.3V±0.2V, providing independent power supply for the system during transit. The power display unit collects the remaining power in real time, and issues a charging prompt when it is lower than the preset threshold. The battery is replenished at the transfer point via a 10A charger. During charging, the battery life switch remains off to avoid power supply conflicts.

[0026] The temperature control system consists of a temperature sensor, an electronic thermostat, a refrigeration unit, and a heating unit. The temperature sensor collects the internal temperature in real time and transmits it to the electronic thermostat. The electronic thermostat uses a control algorithm to switch between heating wire on / off states, precisely controlling the compressor and heating wire to manage temperature differences. The refrigeration unit includes a refrigerated DC compressor, a condenser fan, and an evaporator fan, which work together to improve refrigeration efficiency. The heating unit uses a heating wire structure and is equipped with a parameter switch that allows manual switching between on / off states; it is kept on by default to cope with low-temperature environments.

[0027] The safety protection module is centered around an anti-tilt sensor and a control module. The anti-tilt sensor collects and stores the tilt angle of the box in real time, and the control module controls the compressor's start and stop according to a preset angle threshold to prevent compressor failure caused by tilting. When the temperature controller and the tilting module malfunction, an E60 alarm signal is triggered to promptly alert the operator to troubleshoot the fault. The end-of-life switch and the power switch are linked through preset logic to achieve safe switching of power supply modes, preventing power outages or equipment damage caused by misoperation.

[0028] (II) Detailed Control Method Flow The control method of this invention revolves around three core processes: power supply control, temperature control, and safety protection, forming a complete closed-loop control logic, such as... Figure 3 As shown, the specific steps are as follows: 1. Power Supply Control Flow: When the equipment is at the transfer point, close the power switch and open the end-of-life switch. The system switches to the mains power supply branch. The 24V 14A switching power supply converts the mains power to the appropriate voltage, and the DC-DC voltage regulator module outputs a stable 24VDC voltage to power the downstream refrigeration, temperature control, and other units. When switching to the transport state, open the power switch and close the end-of-life switch. The system automatically switches to lithium battery power supply. The DC-DC voltage regulator module regulates the output voltage of the lithium battery pack to ensure stable operation of the downstream circuits. At night or when the equipment is not in use for a long period of time, both switches are opened simultaneously to cut off the system power supply, reduce energy consumption, and protect the equipment. When the lithium battery pack is charging, only the 10A charger and the lithium battery pack are connected, and the end-of-life switch remains open. Charging stops automatically when the charging is complete, and the power display unit updates the power information synchronously.

[0029] 2. Temperature control process: The electronic temperature controller presets the operating temperature. and control temperature difference , The temperature sensor transmits the real-time temperature inside the box. When the heating element is not activated, a single cooling control logic is used: when The electronic thermostat sends a closing signal to start the compressor, condenser fan, and evaporator fan, thus activating the cooling mode; when A disconnect signal is sent to stop the cooling unit from operating. When the heating element is activated, a cooling-heating coordinated control logic is used: the cooling control upper threshold is consistent with the upper threshold when the heating element is not activated, i.e. Start the cooling system. Stop cooling; heating control is set to... As the activation threshold, Start the heating wire at the time. Heating is stopped when the temperature is high, and temperature is kept stable through two-way control. nearby.

[0030] 3. Safety protection process: The anti-tilt sensor continuously collects the tilt angle of the equipment. Preset compressor stop threshold and recovery threshold ,and .when The control module immediately sends a stop signal to shut down the compressor, preventing tilting that could lead to abnormal compressor lubricating oil circulation and component wear; when The control module initiates a 3-minute delay program. After the delay ends, it sends a recovery signal to restart the compressor, preventing frequent angle fluctuations from causing frequent start-stop operations. If communication between the temperature controller and the tilting module is interrupted or the signal is abnormal, the control module immediately triggers an E60 alarm signal to remind operators to check the wiring connection or module fault, ensuring the safe operation of the equipment.

[0031] (III) Examples Example 1: Room Temperature Medical Sample Transportation Scenario This embodiment is suitable for transporting medical samples at room temperature (2℃-8℃), and is applicable to short-distance transport within cities. The ambient temperature range is 10℃-30℃. There is no need to activate the heating function; the temperature is maintained solely by the refrigeration unit.

[0032] Electrical system configuration: 24V 60Ah lithium battery pack, full charge voltage 29.3V, power warning threshold set to 20%; 24V 14A switching power supply with conversion efficiency ≥90% for the mains power supply branch, 10A charger charging time ≤6h; temperature sensor accuracy ±0.1℃, electronic temperature controller preset. , , The anti-tilt sensor angle threshold is set to... , The heating wire parameter switch is set to the off state, and the DC-DC voltage regulator module output accuracy is ±0.5V.

[0033] Operating Procedure: At the transfer point, connect to mains power, close the power switch, and disconnect the end-of-life switch. The system is powered by the mains power branch, and the cooling unit starts, lowering the internal temperature to 5°C. After switching to transport mode, disconnect the power switch and close the end-of-life switch. The lithium battery pack powers the system, and the temperature sensor collects the temperature in real time. When the internal temperature rises to 6°C, the electronic temperature controller detects this. Start the compressor, condenser fan, and evaporator fan to begin cooling; when the temperature drops to 3.5℃, it is detected that... The refrigeration unit stops operating. During transport, the anti-tilt sensor monitors the angle in real time. When the vehicle turns and the tilt angle reaches 30°, the control module immediately stops the compressor; when the angle returns to below 15°, the compressor restarts after a 3-minute delay. The power display unit provides real-time feedback on the power level. When the power level drops below 20%, a charging prompt is issued. Upon arrival at the next transfer point, the battery is charged via a 10A charger. The battery life switch remains off during charging. After charging is complete, the voltage stabilizes at 29.3V±0.2V, meeting the power supply requirements for subsequent transfers. In this embodiment, the internal temperature fluctuation range is controlled within 3.5℃-6℃, and a single full charge of the lithium battery pack can support 8 hours of continuous transfer, fully adapting to the needs of short-distance sample transfer in urban areas.

[0034] Example 2: Low-Temperature Drug Transport Scenario This embodiment is suitable for transporting medicines at temperatures between 0℃ and 5℃, and is applicable to outdoor transport in northern winters with an ambient temperature range of -10℃ to 15℃. It requires the heating wire and the refrigeration unit to work together to maintain a stable temperature inside the box.

[0035] Electrical system configuration: The lithium battery pack is 24V 60Ah, with a full-charge voltage of 29.3V and a power warning threshold set to 25%; the 24V 14A switching power supply for the mains power supply branch has a low-temperature start function, and the 10A charger supports low-temperature charging protection; the temperature sensor accuracy is ±0.1℃, and the electronic temperature controller is preset. , , The anti-tilt sensor angle threshold is set to... , The heating wire has a power of 50W, the parameter switch is kept on by default, and the DC-DC voltage regulator module has a low-temperature voltage regulation compensation function with an output accuracy of ±0.3V.

[0036] Operating Process: At the transfer point, the system is powered by mains electricity. After startup, the heating element and cooling unit work together to quickly raise the internal temperature to 2°C. During transport, the system switches to lithium battery power. The low ambient temperature causes the internal temperature to drop. When the temperature drops to 0.8°C, the electronic temperature controller detects this. The heating element is activated; when the temperature reaches 2℃, the heating element stops operating. If direct sunlight causes the internal temperature to rise to 2.8℃, it will be detected. The refrigeration unit is activated; refrigeration stops when the temperature drops to 2°C. During transport, if the vehicle encounters a bumpy road and the tilt angle reaches 25°, the control module stops the compressor; once the angle returns to below 12°, the compressor restarts after a 3-minute delay. If communication between the temperature controller and the tilting module is interrupted, an E60 alarm signal is immediately triggered, and the operator stops the vehicle and checks the wiring connections. The lithium battery pack's range is slightly reduced in low-temperature environments; a single full charge can support 6 hours of continuous transport. A warning is issued when the battery level drops to 25%. When charging at the transport point, the charger activates low-temperature protection to prevent overcharging and damage to the lithium battery pack. In this embodiment, the internal temperature fluctuation range is controlled between 0.8°C and 2.8°C, meeting the temperature stability requirements for drug transport in low-temperature environments.

[0037] Example 3: Long-distance, cross-regional medical supply transportation scenario This embodiment is suitable for long-distance transportation of medical supplies at temperatures between 2℃ and 6℃, and is applicable to high-speed transportation across cities. The ambient temperature range is 5℃ to 35℃. It is necessary to ensure long-term power supply stability and temperature control accuracy, and to frequently switch between mains power and lithium battery power.

[0038] Electrical system configuration: The lithium battery pack is 24V 60Ah, with a full-charge voltage of 29.3V. It features dual lithium battery packs for alternating power supply, and a power warning threshold of 30%. The mains power supply branch uses a 24V 14A switching power supply supporting wide voltage input. The 10A charger has fast charging capabilities, with a charging time of ≤4.5 hours. The temperature sensor accuracy is ±0.05℃, and the electronic temperature controller has preset parameters. , , The anti-tilt sensor angle threshold is set to... , The heating wire has a power of 80W, and the parameter switch can be manually switched according to the ambient temperature. The DC-DC voltage regulator module has overload protection and an output accuracy of ±0.2V. The power display unit supports simultaneous display of dual battery power.

[0039] Operating Process: At the originating transfer point, mains power is connected, and both lithium battery packs charge simultaneously. The battery life switch is off during charging. Charging is complete after 4.5 hours, with the voltage stabilizing at 29.3V±0.2V. During transport, the first lithium battery pack is activated, and the electronic temperature controller initiates its high-precision temperature control logic. When the internal temperature reaches 4.5℃, The cooling unit is activated; when the temperature drops to 3.2℃, The cooling unit is stopped. With a suitable ambient temperature, the heating wire parameter switch is set to the off position. Upon reaching a service area transfer point, the system switches to mains power, simultaneously charging the first lithium battery pack and activating the second lithium battery pack as a backup to prevent power interruption. During high-speed travel, if a sharp bend occurs and the tilt angle reaches 35°, the control module stops the compressor; once the angle returns to below 18°, the compressor restarts after a 3-minute delay to ensure safe operation. During long-distance transport, the power display unit synchronizes the power levels of both battery packs in real time. When the first battery level drops to 30%, the operator is alerted to switch to the second battery pack, with the first battery replenished at subsequent transfer points. In this embodiment, the internal temperature fluctuation range is controlled between 3.2℃ and 4.5℃, and the alternating power supply of the two lithium battery packs supports 16 hours of continuous transport, fully meeting the needs of long-distance cross-city medical supply transport.

[0040] The advantages of the electrical system and control method for the medical vehicle-mounted constant temperature preservation box proposed in this invention are as follows: This invention effectively solves the core pain points of unstable power supply and insufficient battery life in vehicle-mounted transportation scenarios through a dual-power supply module and linkage control logic design, significantly improving the adaptability and reliability of the equipment. The dual-power supply branch can achieve seamless switching between AC mains power and lithium battery pack. AC mains power supply meets the needs of fixed transportation points, and the combination of a 24V 14A switching power supply and a 10A charger ensures power conversion efficiency and lithium battery pack charging safety. The 24V 60Ah lithium battery pack, with real-time power monitoring and early warning functions, can support long-term continuous transportation on a single full charge. The dual-battery alternating power supply scheme is more suitable for cross-regional and long-distance needs. At the same time, the DC-DC voltage regulator module continuously outputs a stable 24VDC voltage, avoiding damage to downstream temperature control, sensing and other precision circuits caused by voltage fluctuations, ensuring continuous and stable operation of the equipment in complex vehicle-mounted environments.

[0041] This invention achieves high-precision temperature control within the enclosure through a segmented temperature control algorithm and a collaborative control strategy, meeting the stringent temperature requirements for medical samples and pharmaceuticals. The electronic temperature controller switches control logic based on the heating wire's activation status, precisely controlling the start and stop timing of the cooling and heating units using preset operating point temperatures and temperature difference parameters. The heating wire is on by default and supports manual switching, flexibly adapting to different ambient temperature scenarios. Compared to traditional single-temperature control modes, this invention, through bidirectional collaborative control of cooling and heating, keeps temperature fluctuations within a smaller range. Combined with real-time feedback from high-precision temperature sensors, it ensures the internal temperature remains stable within the preset range, effectively preventing deterioration or failure of medical supplies due to temperature fluctuations and improving the safety of supplies during transport.

[0042] This invention integrates multiple safety protection mechanisms and a user-friendly control design, balancing equipment safety and ease of operation, and possesses strong practical value. The anti-tilt sensor and control module work together to form a closed-loop protection system. Through preset dual-angle thresholds and delayed recovery logic, compressor malfunctions are prevented under tilt conditions. The E60 alarm signal triggered in case of communication abnormalities promptly alerts operators to troubleshoot the problem. The clear linkage logic between the endurance switch and the power switch reduces the risk of power outages or equipment damage due to misoperation. The design of the heating wire parameter switch and power display unit further enhances the ease of operation. The overall system has a compact structure and clear control logic, making it suitable for various transport scenarios, including short-distance urban transport, low-temperature environments, and long-distance cross-regional transport. It also ensures the safety and stability of medical supply transport throughout the entire process, and has broad application prospects.

[0043] The foregoing has shown and described 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 embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An electrical system for a vehicle-mounted constant temperature storage box for medical use, characterized in that, It includes a dual power supply module, a DC-DC voltage regulator module, a power display unit, a battery life switch, a power switch, a cooling unit, a heating unit, a temperature sensor, an anti-tilt sensor, an electronic temperature controller, and a control module; The dual power supply module includes a 220VAC AC mains power supply branch and a lithium battery pack power supply branch. The AC mains power supply branch is connected to the system via a 24V 14A switching power supply, and the lithium battery pack power supply branch is connected to a charging power supply via a 10A charger. The DC-DC voltage regulator module is connected to the dual power supply module and the subsequent circuit, respectively, and is used to stably output the input power to DC24V; the power display unit is connected to the lithium battery pack and is used to monitor the power of the lithium battery pack in real time. The battery life switch and power switch are linked with the dual power supply module to achieve power supply mode switching; the temperature sensor and anti-tilt sensor are respectively connected to the electronic temperature controller and the control module; the electronic temperature controller is respectively connected to the cooling unit and the heating unit; the control module is linked with the dual power supply module, the anti-tilt sensor and the electronic temperature controller to achieve anti-tilt protection control and power supply logic control. The refrigeration unit includes a refrigerated DC compressor, a condenser fan, and an evaporator fan. The heating unit includes a heating wire. The electronic temperature controller achieves precise start-stop control of the refrigeration unit and the heating unit through a control algorithm.

2. The electrical system of the medical vehicle-mounted constant temperature storage box according to claim 1, characterized in that, The lithium battery pack has a specification of 24V 60Ah. The 24V 14A switching power supply of the mains power supply branch is used to convert 220VAC to 24VDC. The 10A charger has an input voltage of 220VAC and an output voltage of 24VDC and is used to charge the lithium battery pack.

3. The electrical system of the medical vehicle-mounted constant temperature storage box according to claim 1, characterized in that, The control logic for the battery life switch and the power switch is as follows: When switching to transport mode, disconnect the power switch and close the end-of-life switch; the system will then switch to lithium battery power. When the mains power supply is used or the customer's lithium battery pack is used to generate 220VAC power, close the power switch and disconnect the end-of-life switch to switch the system to the mains power supply branch. When not using the device at night or for an extended period of time, simultaneously disconnect the battery life switch and the power switch. During the charging process of the lithium battery pack, the battery life switch remains off.

4. The electrical system of the medical vehicle-mounted constant temperature storage box according to claim 1, characterized in that, The heating wire is equipped with a parameter switch, which is on by default. The heating wire function can be manually turned off or on using the parameter switch.

5. The electrical system of the medical vehicle-mounted constant temperature storage box according to claim 1, characterized in that, The DC-DC voltage regulator module has a constant output voltage of DC24V, which is used to provide a stable power supply to downstream circuits such as the refrigeration DC compressor drive board, condenser fan, evaporator fan, and electronic temperature controller, so as to avoid damage to downstream circuits caused by voltage fluctuations.

6. A control method for the electrical system of a medical vehicle-mounted constant temperature storage box according to any one of claims 1-5, characterized in that, Includes the following steps: (1) Dual power supply switching control: When the transfer point is connected to the mains power 220VAC, the system is powered through the mains power supply branch; during the transfer, the power supply is switched to the lithium battery pack power supply branch, and the system is powered through the lithium battery pack. (2) Power monitoring and charging control: The power information of the lithium battery pack is collected in real time through the power display unit. When the power is insufficient, the power of the lithium battery pack is replenished by a 10A charger at the transfer point. During the charging process, the end-of-life switch is disconnected. (3) Precise control of cooling and heating: The electronic temperature controller controls the start and stop of the cooling unit and the heating unit by means of the real-time temperature collected by the temperature sensor, combined with the preset working point temperature St, the control temperature difference rd1 and rd2, and the control algorithm. (4) Anti-tilt protection control: The control module collects the tilt angle of the storage box in real time through the anti-tilt sensor. When the tilt angle meets the preset threshold condition, the compressor of the refrigeration unit is controlled to start and stop. When the temperature controller communicates abnormally with the tilting module, an alarm is triggered.

7. The control method for the electrical system of the medical vehicle-mounted constant temperature preservation box according to claim 6, characterized in that, In step (3), when the heating wire is not activated, the control algorithm for the refrigeration unit is as follows: When real-time temperature At this time, the electronic thermostat sends a switch-off signal to control the compressor to stop working; When real-time temperature At that time, the electronic temperature controller sends a switch closure signal to control the compressor to start working; in, To preset the operating point temperature, , The temperature difference is preset to control the temperature difference.

8. The control method for the electrical system of the medical vehicle-mounted constant temperature preservation box according to claim 6, characterized in that, In step (3), when the heating wire is activated, the control algorithms for the cooling unit and the heating unit are as follows: Cooling control: when the real-time temperature When the electronic thermostat sends a switch-off signal, it controls the compressor to stop working; when the real-time temperature... At that time, the electronic temperature controller sends a switch closure signal to control the compressor to start working; Heating control: When the real-time temperature When the electronic temperature controller closes the power supply to the heating wire, it controls the heating wire to start heating; when the real-time temperature... When this happens, the electronic temperature controller disconnects the power supply to the heating wire, stopping the heating wire from heating. in, To preset the operating point temperature, , The temperature difference is preset to control the temperature difference.

9. The control method for the electrical system of the medical vehicle-mounted constant temperature preservation box according to claim 6, characterized in that, The specific logic of the anti-tilt protection control described in step (4) is as follows: When the anti-tilt sensor detects the tilt angle of the storage box When this happens, the control module sends a stop signal to stop the compressor from working; When the anti-tilt sensor detects the tilt angle of the storage box When the delay occurs, the control module initiates a delay program, and after a 3-minute delay, sends a recovery signal to control the compressor to resume operation. When a communication failure occurs between the temperature controller and the tilting module, the control module triggers an E60 alarm signal; in, The tilt angle threshold at which the compressor stops. The tilt angle threshold for resuming compressor operation, and .

10. The control method for the electrical system of the medical vehicle-mounted constant temperature preservation box according to claim 6, characterized in that, The full-charge voltage of the lithium battery pack in step (2) is 29.3V±0.2V. The power display unit provides real-time feedback on the remaining power of the lithium battery pack through the power display progress module. When the remaining power is lower than the preset threshold, a charging prompt signal is issued to remind the user to replenish the power of the lithium battery pack at the transfer point.

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