Multi-mode second-level thermal switch and dynamic thermal management system and method thereof

Abstract

The invention belongs to the technical field of ultra-precision measurement, and discloses a multi-mode second-level thermal switch and a dynamic thermal management system and method.The multi-mode second-level thermal switch comprises a flow channel system and an electric field driving system, and the flow channel system comprises a first flow channel and a second flow channel which are independent of each other; the first flow channel and the second flow channel are filled with heat-conducting media, the electric field driving system comprises electrodes arranged on the two sides of the first flow channel and the second flow channel, flow channel mazes are arranged in the first flow channel and the second flow channel, and the ends, close to the electrodes, of the flow channel mazes are connected with the electrodes; spatial distribution and replacement of a heat-conducting medium in the double-layer flow channel can be accurately driven in a non-contact mode, so that the heat conduction state is rapidly switched within second-level time, and second-level rapid switching of the heat conduction state is achieved; and the control precision of medium space distribution is effectively improved, heat flow regulation and control can be graded according to needs, and multi-mode fine management is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ultra-precision measurement, and in particular to a multi-modal second-level thermal switch and a dynamic thermal management system and method thereof. BACKGROUND

[0002] With the breakthrough of high-end manufacturing field to sub-micron, nanometer level precision, the core equipment such as numerical control machine tools and lithography machines have put forward strict requirements for the thermal environment stability of key functional components. Any short-time thermal disturbance may be converted into obvious machining or measuring error. As a core component, the grating displacement sensor (hereinafter referred to as "grating") for displacement precision detection in the equipment directly determines the overall performance of the equipment. However, the grating is sensitive to local thermal disturbance during service, and its measurement accuracy is easily affected. Taking a numerical control machine tool as an example, the servo motor of the feeding system will continuously generate heat during operation. The local temperature rise can reach 5-8℃ under high-speed start-stop or heavy load transient conditions. These heat will be directly conducted to the ball screw, causing the screw to heat and elongate, and the worktable displacement detected by the grating ruler will form a positioning error. In addition, the motor as a heat source will heat the nearby bed structure, and even cause the installation base surface of the grating ruler to expand unevenly. A 5℃ local temperature fluctuation can cause a 5μm / m deformation error of the metal-based grating, changing the periodicity of the grating pitch (the pitch and parallelism of the grating line), causing reading drift and positioning error. In dynamic measurement scenarios, such errors will further accumulate, which cannot meet the measurement target of micron level and higher precision, and becomes the core bottleneck restricting the upgrade of grating sensors to higher precision.

[0003] Traditional thermal control methods are difficult to carry out accurate thermal control in a local area (such as heat pipes and fans). For the above thermal control needs, a new type of thermal control scheme relying on the double-mode response of material constitutive change or external field triggering can realize the bidirectional regulation of heat flow under certain conditions, thereby making directional adjustment to the local heat flow. However, the response time of this type of technology is relatively long, and it is difficult to realize rapid suppression and compensation of second-level or sub-second level pulse heat flow caused by instantaneous start-stop or speed regulation of the motor. At the same time, most traditional thermal switches are double-mode (full-on / full-off) switches, and the freedom degree is limited, which cannot realize the step-by-step and multi-modal regulation of heat. It is difficult to balance between maintaining measurement accuracy and efficient heat dissipation / heat blocking. For example, when the numerical control machine tool is feeding at low speed, only low-flux heat flow blocking is needed to meet the demand. The traditional "complete blocking" state will cause excessive thermal management, increase additional energy consumption, and even cause fluctuations in the precision of the equipment.

[0004] Therefore, it is urgent to design a new technology that can solve the problems of long thermal control time and inability to realize step-by-step and multi-modal regulation of heat. SUMMARY

[0005] The present application aims to provide a multi-modal second-level thermal switch and a dynamic thermal management system and method thereof to overcome the problems in the prior art.

[0006] To achieve the above-mentioned purposes, the technical solutions adopted by the present application are as follows: In a first aspect, the present application provides a multi-modal second-level thermal switch, comprising: A flow channel system comprising a first flow channel and a second flow channel independent of each other, the first flow channel being located at the top of the second flow channel, and the interiors of the first flow channel and the second flow channel being filled with a heat-conducting medium; An electric field driving system comprising electrodes arranged on both sides of the first flow channel and the second flow channel, and a flow channel labyrinth being arranged in the interiors of the first flow channel and the second flow channel, one end of the flow channel labyrinth being connected with the electrodes.

[0007] According to an embodiment of the present application, one side of the first flow channel and the second flow channel is connected with a branch structure, and one side of the electrodes is located outside the branch structure and connected with the flow channel labyrinth inside the branch structure.

[0008] According to an embodiment of the present application, the branch structure is a physical dendritic structure.

[0009] According to an embodiment of the present application, the side portions of the first flow channel and the second flow channel and the outside of the branch structure are provided with gas overflow holes, and the gas overflow holes are attached with hydrophobic gas-permeable films.

[0010] According to an embodiment of the present application, the flow channel labyrinth comprises an access section, one end of the access section being connected with the electrodes, the other end of the access section being connected with a V-shaped section, the V-shaped section being connected with an exit section, and the exit section being connected with the first flow channel or the second flow channel.

[0011] In a second aspect, the present application provides a multi-modal second-level thermal switch dynamic thermal management system based on the multi-modal second-level thermal switch of the above-mentioned embodiments, comprising: A grating sensor in contact with the top of the first flow channel; A temperature sensor network comprising a heat source temperature sensor and a ruler body temperature sensor, the ruler body temperature sensor being located on the grating ruler body of the grating sensor; A heat source, the heat source temperature sensor being located at the heat source; The control system is signal-connected to the heat source temperature sensor and the scale body temperature sensor, and electrically connected to the electrode.

[0012] Thirdly, the present invention also provides a multimodal, second-level thermal switch dynamic thermal management method. The multimodal, second-level thermal switch dynamic thermal management system based on the above embodiments includes the following steps: The temperature sensing network monitors the temperature status in real time and transmits the temperature signal to the control system. The control system receives the temperature signal, generates a control command based on the temperature signal, and sends the control command to the electric field drive system. The electric field drive system receives the control command and, based on the control command, drives the flow channel system to transfer heat to the grating sensor, thereby achieving dynamic thermal management.

[0013] According to one embodiment of the present invention, the temperature sensing network monitors the temperature status in real time and transmits the temperature signal to the control system, specifically including: The heat source temperature sensor and the scale body temperature sensor respectively detect the temperature signal of the heat source and the temperature signal of the grating sensor, and transmit the temperature signal of the heat source and the temperature signal of the grating sensor to the control system.

[0014] According to one embodiment of the present invention, the control system receives the temperature signal, generates a control command based on the temperature signal, and sends the control command to the electric field drive system, specifically including: The control system receives the temperature signal from the heat source and the temperature signal from the grating sensor, generates a control command based on the temperature signal from the heat source and the temperature signal from the grating sensor, and sends the control command to the electrode.

[0015] According to one embodiment of the present invention, the electric field driving system receives the control command and, based on the control command, drives the flow channel system to transfer heat to the grating sensor, thereby realizing dynamic thermal management, specifically including: The electrode receives the control command and, based on the control command, drives the thermally conductive medium to change its spatial position within the first and second flow channels, thereby achieving dynamic thermal management of the multimodal second-level thermal switch. The dynamic thermal management includes: High thermal conductivity (overcooling protection): When the grating sensor needs heat to maintain its optimal operating temperature during low-temperature operation or equipment startup, the thermally conductive medium simultaneously fills the first and second channels, establishing an efficient thermal conduction path from the heat source to the grating sensor. This allows the heat from the first and second channels to be quickly transferred to the grating sensor, effectively preventing the sensor from overcooling. Adjustable medium thermal conductivity state (fine temperature control): When under medium load or temperature fluctuation conditions, the thermally conductive medium fills the first flow channel and leaves the second flow channel at the same time, allowing the heat of the first flow channel to be transferred to the grating sensor; or, the thermally conductive medium leaves the first flow channel and fills the second flow channel at the same time, allowing the heat of the second flow channel to be transferred to the grating sensor. High thermal resistance state (overheat protection): When under high temperature or heavy load conditions, and a large amount of heat is generated by potential heat sources, the thermally conductive medium leaves the first flow channel and the second flow channel at the same time. At this time, the heat flow path is dominated by the low thermal conductivity matrix material, forming an efficient thermal insulation barrier, which prevents heat from being transferred from the first flow channel and the second flow channel to the grating sensor to the greatest extent, ensuring that its core accuracy is not affected by overheating.

[0016] The above technical solution has the following advantages or beneficial effects: Firstly, this invention provides a multimodal, second-level thermal switch. Through an innovative dual-layer independent flow channel structure and non-contact electric field driving technology, it achieves a significant breakthrough in thermal management performance, successfully solving the problems of slow response speed and single control mode in traditional thermal control devices. Its core lies in using electric field force to precisely drive the spatial distribution and displacement of the heat-conducting medium within the dual-layer flow channel in a non-contact manner, thereby rapidly switching the thermal conductivity state within seconds. This achieves second-level rapid switching of the thermal conductivity state, effectively solving the inherent limitations of traditional thermal switches that are slow to respond and can only achieve binary "on / off" control. It effectively improves the control accuracy of the medium spatial distribution, enabling heat flow control to be graded as needed, and realizing multimodal fine management. This technology can provide dynamic and efficient active thermal protection for precision components such as grating sensors that are extremely sensitive to temperature fluctuations. It is particularly suitable for high-precision CNC machine tools, lithography machines, and other high-end equipment with instantaneous start-stop and drastic load changes. Its application can effectively suppress instantaneous thermal shock and cumulative thermal errors, ensuring the long-term operating accuracy and stability of equipment under complex working conditions, demonstrating clear application value and broad prospects for promotion.

[0017] In some embodiments, the present invention achieves physical isolation between the electrodes and the heat-conducting medium within the flow channel by setting a branch structure on one side of the flow channel and arranging the electrodes outside the branch structure while placing the flow channel labyrinth connected to it inside the branch structure. This avoids direct contact between the electrodes and the heat-conducting medium, eliminating the risks of electrode short circuits, corrosion, or performance degradation caused by medium leakage, ion migration, or electrochemical reactions. This structure significantly improves the long-term operational stability and reliability of the electric field drive system, ensuring the accuracy and consistency of non-contact drive, and providing a key guarantee for the thermal switch to maintain second-level response and multi-modal control capabilities under long-term complex operating conditions. At the same time, it also reduces the stringent requirements for the insulation performance of the heat-conducting medium, broadens the range of medium selection, and thus enhances the feasibility and economy of the overall design while ensuring the long-term stable operation of the device.

[0018] In some embodiments, the branch structure adopts a physical dendritic design. By simulating the efficient fractal principle in nature, its geometric asymmetry amplifies the difference in thermal conductivity between "with high thermal conductivity medium" and "without high thermal conductivity medium". This allows the switch to conduct heat more efficiently in the "on" state and to insulate heat more effectively in the "off" state. This significantly enhances the control capability and contrast of the entire thermal switch between the heat conduction and heat insulation states, providing key support for the thermal switch to achieve reliable multi-mode switching on a second-level timescale.

[0019] In some embodiments, the present invention achieves effective discharge of gas accumulated inside the device by opening gas overflow holes on the side of the flow channel and outside the branch structure and attaching a hydrophobic and breathable membrane. This is used to maintain the pressure balance inside and outside the flow channel and discharge the gas generated by the electrochemical reaction, that is, to discharge the hydrogen gas generated by the electrochemical reaction and maintain the pressure balance inside and outside the flow channel, thereby ensuring the electric field driving efficiency and thermal switching stability, and thus ensuring the long-term reliable operation of the thermal switch in the multi-modal control process.

[0020] In some embodiments, the present invention designs a specific flow channel labyrinth structure including an inlet section, a V-shaped section, and an outlet section. By using a large-angle bend structure, the present invention utilizes the difficulty (flow resistance) of a high thermal conductivity medium (such as liquid metal) passing through a large-angle bend in a microchannel. Without introducing additional components, it effectively avoids unintended contact between liquid metal and electrodes, simplifying the system structure.

[0021] Secondly, this invention provides a multimodal, second-level dynamic thermal management system for thermal switches. By deeply integrating the core thermal switch with a temperature sensing network and an intelligent control system, it achieves real-time, proactive thermal protection for key components such as grating sensors. The system continuously monitors temperature changes in key areas using temperature sensors placed on the heat source and the grating scale, and transmits the data to the control system in real time. The control system dynamically generates control commands based on a preset algorithm, precisely driving the electrodes of the thermal switch, thereby adjusting the spatial distribution of the heat-conducting medium in the double-layer flow channel within seconds and changing the equivalent thermal conductivity of the system. Closed-loop control enables the system to actively suppress the conduction effect of heat source fluctuations on the grating sensor, effectively compensate for thermal errors, and provide a reliable guarantee for the long-term stable operation of high-precision measurement equipment under varying operating conditions.

[0022] Thirdly, this invention provides a multimodal, second-level dynamic thermal management method for thermal switching, achieving real-time and precise thermal protection for grating sensors. This method first continuously monitors key temperature signals of the heat source and the grating scale via a temperature sensing network and transmits them to the control system in real time. The control system, based on the received temperature data and a preset thermal management strategy, generates corresponding control commands and sends them to the electric field drive system. The electric field drive system precisely adjusts the electric field applied to the electrodes according to the commands, thereby driving the heat-conducting medium within the double-layer flow channel to rapidly redistribute spatially, changing the system's heat conduction path and efficiency within seconds, thus intelligently controlling the heat flowing to the grating sensor. The closed-loop control process realizes full-link dynamic thermal management from temperature sensing and intelligent decision-making to rapid execution, effectively suppressing temperature fluctuations and ensuring the measurement accuracy and long-term stability of the grating sensor under complex operating conditions.

[0023] In some embodiments, the present invention constructs a complete temperature monitoring network by deploying temperature sensors on the heat source and the scale of the grating sensor. The heat source temperature sensor collects the temperature change signal of the heat source in real time, and the scale temperature sensor synchronously monitors the temperature status of key parts of the grating sensor. The two sets of temperature signals are transmitted to the control system in real time, providing a comprehensive and accurate data foundation for thermal management decisions. The dual-point temperature monitoring mechanism can accurately capture the correspondence between heat source fluctuations and sensor temperature rise, laying a key data foundation for subsequent multi-modal and graded precise thermal regulation, thereby ensuring that the entire system can make a fast and accurate thermal response.

[0024] In some embodiments, the control system simultaneously receives real-time temperature signals from both the heat source and the grating sensor. By analyzing these two key data sources, it accurately determines the current thermal environment state and heat transfer requirements. Based on this, the system intelligently generates corresponding control commands and precisely sends them to the electrodes of the electric field drive system. This enables rapid and accurate conversion from multi-source temperature sensing to electric field drive signals, providing precise decision-making basis for core thermal management actions and ensuring the reliability and timeliness of dynamic thermal management closed-loop control.

[0025] In some embodiments, the present invention achieves dynamically switchable thermal management modes by controlling the spatial distribution of the thermally conductive medium within the dual-layer flow channels through electrodes: under low-temperature conditions, the medium simultaneously fills the upper and lower flow channels, and the system is in a low-resistance thermal state, allowing sufficient heat transfer to the grating sensor; under medium-temperature conditions, the medium fills only one flow channel, and the system switches to a medium thermal resistance state, achieving graded adjustment of heat; under high-temperature conditions, the medium completely leaves both flow channels, and the system enters a high-resistance thermal state, blocking heat transfer; this method achieves second-level, multi-modal active thermal protection for the grating sensor through precise control of the medium position. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of a multimodal, second-level thermal switch structure according to some embodiments of this specification; Figure 2 This is a cross-sectional view of the flow channel labyrinth shown according to some embodiments of this specification; Figure 3 This is a schematic diagram of the structure of a multimodal, second-level thermal switch dynamic thermal management system according to some embodiments of this specification; Figure 4 This is a time comparison chart of the thermally conductive medium filling state shown in some embodiments of this specification; Figure 5 This is a comparison chart of the time it takes for the heat-conducting medium to leave its state, as shown in some embodiments of this specification. Figure 6 This is a schematic diagram of the forward output temperature of a multimodal second-level thermal switch according to some embodiments of this specification; Figure 7 This is a schematic diagram of the reverse output temperature of a multimodal second-level thermal switch according to some embodiments of this specification; In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. External support; 2. Electrode; 3. Flow labyrinth; 31. Inlet section; 32. V-shaped section; 33. Outlet section; 4. First flow channel; 5. Second flow channel; 6. Hydrophobic and breathable membrane; 7. Heat source; 8. CNC machine tool; 9. Grating sensor; 10. Control system; 11. Heat source temperature sensor; 12. Body temperature sensor. Detailed Implementation

[0027] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0028] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used 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 limitations on this invention.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0030] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," 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, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] 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.

[0033] Example: This invention provides a multimodal, second-level thermal switch and its dynamic thermal management system and method, which can adapt to the dynamic heating characteristics of potential heat sources 7 and achieve the matching of thermal control with actual needs.

[0034] This invention provides a multimodal, second-level thermal switch. Figure 1 The diagram below shows a multimodal second-level thermal switch structure according to some embodiments of this specification. The multimodal second-level thermal switch includes a flow channel system and an electric field drive system. The flow channel system includes a first flow channel 4 and a second flow channel 5 that are independent of each other. The first flow channel 4 is located at the top of the second flow channel 5 and forms an independent working chamber in the second flow channel 5. The interior of the first flow channel 4 and the second flow channel 5 (i.e., both working chambers) is filled with a heat-conducting medium. The electric field driving system includes electrodes 2 disposed on both sides of the first flow channel 4 and the second flow channel 5, which are used to drive the thermally conductive medium to change its spatial position within the first flow channel 4 and the second flow channel 5 through electrochemical action, that is, to control the thermally conductive medium to enter or leave the corresponding working chamber, thereby realizing the second-level switching of the thermal switching state; both the first flow channel 4 and the second flow channel 5 are provided with a flow channel labyrinth 3, and one end of the flow channel labyrinth 3 near the electrode 2 is connected to the electrode 2 to prevent the thermally conductive medium from contacting the electrode 2.

[0035] In some embodiments, a branch structure is connected to one side of the first flow channel 4 and the second flow channel 5, wherein the electrode 2 on one side is located outside the branch structure, and the flow channel labyrinth 3 connected to the electrode 2 on one side is located inside the branch structure and is connected to the first flow channel 4 or the second flow channel 5 through the branch structure.

[0036] In some embodiments, the first flow channel 4 is the upper flow channel and the second flow channel 5 is the lower flow channel, which can also be referred to as the flow channel in the heat transport path matrix. The heat transport path matrix is ​​integrally formed by photosensitive resin through stereolithography 3D printing technology and has low thermal conductivity.

[0037] In some embodiments, the thermal conductivity of the photosensitive resin is less than 0.3 W / m·K.

[0038] In some embodiments, the thermally conductive medium is a high thermal conductivity medium, which has high thermal conductivity and flowability characteristics, and is pre-filled in the first flow channel 4 and the second flow channel 5.

[0039] In some embodiments, the high thermal conductivity medium includes, but is not limited to, liquid metals such as gallium indium alloy and gallium indium tin alloy, as well as electrolyte solutions.

[0040] In some embodiments, the liquid metal is preferably an EGaIn alloy with a melting point of 16 °C, and the electrolyte solution is preferably a 0.5 mol / L NaOH solution.

[0041] In some embodiments, the volumes of the two flow channels are optimized to differ in order to achieve better thermal regulation capabilities, wherein the total volume of the first flow channel 4 is 450 mm. 3 Up to 550 mm 3 The second flow channel 5 is 850 mm. 3 Up to 900 mm 3 .

[0042] In some embodiments, the branching structure is a biomimetic physical tree-like structure found in nature.

[0043] In some embodiments, the physical branches include plant roots, lightning, etc.

[0044] In some embodiments, the branching structure is a slope-reducing branching structure designed based on the principle of phonon asymmetric scattering, which is used to enhance the forward transport of heat flow and suppress the reverse transport, thereby achieving bidirectional asymmetric thermal regulation.

[0045] In some embodiments, heat flows in the forward direction, i.e., heat flows outward along the branch structure, and heat flows in the reverse direction, i.e., heat flows inward along the branch structure.

[0046] In some embodiments, the parameters of the branch structure are: the volume fraction of the high thermal conductivity filler is 20%-30%, the branch length is 4-6 mm, and the number of branches is 3-5.

[0047] In some embodiments, gas overflow holes are provided on the sides of the first flow channel 4 and the second flow channel 5, as well as on the outside of the branch structure. The gas overflow holes are attached with a hydrophobic and breathable membrane 6 to maintain the pressure balance inside and outside the flow channel and to discharge the gas generated by the electrochemical reaction, that is, to discharge the hydrogen gas generated by the electrochemical reaction and maintain the pressure balance inside and outside the flow channel.

[0048] In some embodiments, the diameter of the gas overflow orifice is 3 mm.

[0049] In some embodiments, Figure 2The flow channel labyrinth 3 shown in some embodiments of this specification includes an inlet section 31, one end of which is connected to the electrode 2, and the other end of which is connected to a V-shaped section 32. The V-shaped section 32 is connected to an outlet section 33, which is connected to the first flow channel 4 or the second flow channel 5.

[0050] In some embodiments, the flow channel maze 3 located on one side of the flow channel system is connected to one end of the first flow channel 4 or the second flow channel 5 through the branch structure, and the flow channel maze 3 located on the other side of the flow channel system is connected to the other end of the first flow channel 4 or the second flow channel 5.

[0051] In some embodiments, a curved structure with an angle greater than 90 degrees is provided at the front end of the electrode 2 access point, that is, the included angle between the access section 31 and the V-shaped section 32 is greater than 90 degrees.

[0052] In some embodiments, the included angle between the access segment 31 and the V-shaped segment 32 ranges from 110° to 135°.

[0053] In some embodiments, the angle between the V-shaped segment 32 and the outlet segment 33 is greater than 90 degrees.

[0054] In some embodiments, the included angle between the V-shaped segment 32 and the outlet segment 33 ranges from 110° to 135°.

[0055] In some embodiments, the flow maze 3 is designed with a large-angle bend structure, which takes advantage of the difficulty (flow resistance) of a high thermal conductivity medium (such as liquid metal) passing through a large-angle bend in the microchannel. Without introducing additional components, it effectively avoids unintended contact between the liquid metal and the electrode 2, simplifying the system structure.

[0056] In some embodiments, the electrode 2 is sealed and fixed with epoxy resin to prevent leakage, and the contact length between the electrode 2 and the solution in the first flow channel 4 or the second flow channel 5 is controlled within the range of 1-2 mm.

[0057] In some embodiments, the electrode 2 may be a copper electrode, preferably with a diameter of 2 mm, and adopts a single-sided double electrode design. By applying an external electric field to the electrode 2, the liquid metal can be driven to generate directional movement in the flow channel, thereby realizing the switching of the thermal switch between different thermal conductivity states.

[0058] In some embodiments, a substrate, namely an external support 1, is further provided on the top of the first flow channel 4 and the second flow channel 5 located on one side of the branch structure. The external support 1 is located on the side of the branch structure away from the electrode 2.

[0059] In some embodiments, the external support 1 is preferably made of PLA material.

[0060] In some embodiments, the external support 1 and the flow channel system are complementary structures, connected to the flow channel system substrate by an interference fit, providing mechanical support and structural rigidity for the entire switch.

[0061] In some embodiments, the external support 1 is further designed with a stepped structure to help increase the bidirectional heat transfer temperature difference of the switch and improve its thermal rectification performance.

[0062] In some embodiments, the multimodal second-level thermal switch can suppress the output temperature fluctuation within the range of positive / negative ambient temperature fluctuations under the environmental temperature disturbances of the positive / negative thermal switch.

[0063] In some embodiments, the thermal switch can realize four basic states: fully open, half open, half closed, and fully closed. There are four basic states when heat flows in the forward direction, i.e., heat flow disperses along the branch structure, and there are also four basic states when heat flows in the reverse direction, i.e., heat flow gathers along the branch structure, for a total of eight basic states.

[0064] In some embodiments, when heat flows in the forward direction, the flow channel system is configured to achieve multiple thermal conductivity states, including: fully open state: both the working chambers of the first flow channel 4 (i.e., the upper layer) and the second flow channel 5 (i.e., the lower layer) are filled with a high thermal conductivity medium; half open state: only one working chamber of the first flow channel 4 or the second flow channel 5 is filled with a high thermal conductivity medium; half closed state: only one working chamber of the first flow channel 4 or the second flow channel 5 is not filled with a high thermal conductivity medium; and fully closed state: neither the working chambers of the first flow channel 4 nor the second flow channel 5 is filled with a high thermal conductivity medium.

[0065] In some embodiments, when heat flows in the reverse direction, the flow channel system is configured to achieve multiple thermal conductivity states, including: fully open state: both the working chambers of the first flow channel 4 (i.e., the upper layer) and the second flow channel 5 (i.e., the lower layer) are filled with a high thermal conductivity medium; half open state: only one working chamber of the first flow channel 4 or the second flow channel 5 is filled with a high thermal conductivity medium; half closed state: only one working chamber of the first flow channel 4 or the second flow channel 5 is not filled with a high thermal conductivity medium; and fully closed state: neither the working chambers of the first flow channel 4 nor the second flow channel 5 is filled with a high thermal conductivity medium.

[0066] This invention provides a multimodal, second-level thermal switch dynamic thermal management system, based on the aforementioned multimodal, second-level thermal switch. Figure 3The diagram below shows the structure of a multimodal second-level thermal switch dynamic thermal management system according to some embodiments of this specification. The multimodal second-level thermal switch dynamic thermal management system includes: a grating sensor 9, a temperature sensing network, a heat source 7, and a control system 10. The grating sensor 9 is in contact with the top of the first flow channel 4; the temperature sensing network includes a heat source temperature sensor 11 and a scale body temperature sensor 12, the scale body temperature sensor 12 being located on the grating scale body of the grating sensor 9; the heat source temperature sensor 11 is located on the heat source 7; the control system 10 is signal-connected to the heat source temperature sensor 11 and the scale body temperature sensor 12, and electrically connected to the electrode 2, for receiving signals from the temperature sensing network, generating control commands and sending them to the electrode 2, thereby driving the distribution of the heat-conducting medium through the electrode 2, thereby dynamically adjusting the thermal conductivity state of the multimodal second-level thermal switch.

[0067] In some embodiments, electrode 2 is an electrode pair.

[0068] In some embodiments, this embodiment demonstrates the application of the multimodal second-level thermal switch to a vertical machining center to protect its precision grating ruler from thermally induced accuracy loss caused by heat sources 7 such as the spindle. The multimodal second-level thermal switch is mounted on the bed of the CNC machine tool 8, precisely located between the core heat source 7 (such as the spindle unit) and the precision grating sensor 9, wherein the A-side (high thermal conductivity surface) of the multimodal second-level thermal switch faces the heat source 7, and the B-side (low thermal conductivity surface) faces the grating ruler.

[0069] In some embodiments, the heat source temperature sensor 11 is located near the spindle bearing housing.

[0070] In some embodiments, the temperature sensing network may further include an ambient temperature sensor (not shown in the figure).

[0071] In some embodiments, the control unit 10 is configured to receive signals from the temperature sensing network and, based on the thermal management control logic stored within it, generate control commands and send them to the electrodes 2 of the thermal switch, thereby driving the liquid metal to redistribute and achieving automatic switching of the thermal switch's operating state.

[0072] In some embodiments, the control system 10 can be an MCU control system, with an embedded microcontroller as its core. It acquires signals from the scale body temperature sensor 12 installed near the heat source 7 and on the scale body in real time through an ADC interface, and monitors the changes in the temperature of the heat source 7 and the scale body. The GPIO output pin of the MCU is connected to the electrode 2 in the electric field driving system of the multi-modal second-level thermal switch, and controls the direction and intensity of the electric field between the electrode 2 by outputting digital signals. Based on the preset temperature threshold logic, when the temperature of the heat source 7 rises sharply and the scale body temperature approaches the safety upper limit, the MCU immediately drives the electric field to remove the high thermal conductivity medium from the working chamber and switches to a fully off or half-off state to block the heat flow. Under conditions of small temperature difference or low temperature, the control medium fills the chamber and enters a fully open or half-open state, thereby realizing multi-modal second-level thermal switching, dynamically adjusting the thermal resistance, and effectively protecting the grating sensor 9 from thermal disturbance.

[0073] This invention also provides a multimodal, second-level thermal switch dynamic thermal management method, based on the above-mentioned multimodal, second-level thermal switch dynamic thermal management system, comprising the following steps: Step 1: The temperature sensing network monitors the temperature status in real time and transmits the temperature signal to the control system 10.

[0074] In some embodiments, the specific steps include: the heat source temperature sensor 11 and the scale body temperature sensor 12 respectively detect the temperature signal of the heat source 7 and the temperature signal of the grating sensor 9, and transmit the temperature signal of the heat source 7 and the temperature signal of the grating sensor 9 to the control system 10.

[0075] Step two, the control system 10 receives the temperature signal, generates a control command based on the temperature signal, and sends the control command to the electric field drive system.

[0076] In some embodiments, the control system 10 receives the temperature signal of the heat source 7 and the temperature signal of the grating sensor 9, generates a control command based on the temperature signal of the heat source 7 and the temperature signal of the grating sensor 9, and sends the control command to the electrode 2.

[0077] Step 3: The electric field driving system receives the control command and drives the flow channel system to transfer heat to the grating sensor 9 based on the control command, thereby realizing dynamic thermal management.

[0078] In some embodiments, the method specifically includes: the electrode 2 receiving the control command, and driving the thermally conductive medium to change its spatial position within the first flow channel 4 and the second flow channel 5 based on the control command, thereby realizing dynamic thermal management of the multimodal second-level thermal switch, wherein the dynamic thermal management includes: High thermal conductivity (overcooling protection): When the grating sensor 9 needs heat to maintain the optimal operating temperature during low temperature operation or equipment startup, the thermally conductive medium is controlled to simultaneously fill the working chambers of the first flow channel 4 and the second flow channel 5, establishing an efficient thermal conduction path from the heat source 7 to the grating sensor 9, allowing the heat from the first flow channel 4 and the second flow channel 5 to be quickly transferred to the grating sensor 9, effectively preventing the sensor from overcooling; Adjustable medium thermal conductivity state (fine temperature control): When under medium load or temperature fluctuation conditions, the control system can precisely select one of two sub-states for regulation: Sub-state 1: The heat-conducting medium fills the working chamber of the first flow channel 4 and simultaneously withdraws from the working chamber of the second flow channel 5; Sub-state 2: The heat-conducting medium withdraws from the working chamber of the first flow channel 4 and simultaneously fills the working chamber of the second flow channel 5; Since the first flow channel 4 and the second flow channel 5 have inherent differences in structure and heat capacity, these two sub-states correspond to two different medium-level thermal conductivity, thereby enabling more precise gradient adjustment of heat transfer to match the complex and ever-changing thermal environment requirements; In the high-resistance thermal state (overheat protection), when the machine is in a high-temperature or heavy-load condition, i.e., a high-speed or heavy-cutting machining state, the potential heat source generates a large amount of heat. The thermally conductive medium is controlled to simultaneously withdraw from the working chambers of the first flow channel 4 and the second flow channel 5. At this time, the heat flow path is dominated by the low thermal conductivity matrix material, forming an efficient thermal insulation barrier, which prevents heat transfer to the grating sensor 9 to the greatest extent, ensuring that its core accuracy is not affected by overheating.

[0079] In some embodiments, the control unit 10 controls the thermal switch to operate in at least three modes based on real-time temperature feedback and the operating conditions of the CNC machine tool 8: When in a cold start or low-speed operation state, the thermal switch is in the initial state, with the upper and lower layers of liquid metal completely filling the working channel, making the switch present a low-resistance thermal state, allowing an appropriate amount of heat to be transferred to the grating sensor to meet its normal operating temperature requirements in a low-temperature environment; when in a medium-load machining state, the upper layer of liquid metal is controlled to fill the working channel while the lower layer leaves the working channel, or the upper layer of liquid metal leaves the working channel while the lower layer fills the working channel, making the switch present a medium-resistance thermal state, realizing controllable adjustment of the heat transfer path; when in a high-speed or heavy cutting machining state, the liquid metal in the upper and lower channels is controlled to leave the working channel, making the switch present a high-resistance thermal state, effectively blocking the heat transfer path to the grating sensor 9, and preventing overheating.

[0080] In some embodiments, the method monitors the temperature of the potential heat source 7 or the state of the grating sensor 9; when enhanced heat dissipation is required, the electric field driving system is controlled to drive a high thermal conductivity medium into one or all working chambers to increase the thermal conductivity from the heat source 7 to the sensor; when enhanced insulation is required, the electric field driving system is controlled to drive a high thermal conductivity medium out of one or all working chambers to reduce the thermal conductivity from the heat source 7 to the sensor.

[0081] In some embodiments, a capability verification experiment for the multimodal second-level thermal switch of the present invention is provided. Figure 4 This is a time comparison chart of the thermally conductive medium filling state shown in some embodiments of this specification. Figure 5 To illustrate the time-of-exit comparison of the thermally conductive medium according to some embodiments of this specification, in a specific experimental verification of this invention, to control heat transfer on a shorter timescale, it is necessary to experimentally analyze the output temperature of the thermal switch during the transfer process. The thermal switch is placed on a constant heater at a heating temperature of 70 °C, and encapsulated with a polyimide film (with a high emissivity of 0.95) to ensure consistent thermal emissivity of the thermal switch. An ambient temperature is monitored using a Bluetooth thermometer with an accuracy of 0.01 °C. An infrared camera (FLIR E95) probe is placed in the target area to monitor the surface temperature of the switch.

[0082] During the experiment, a 12V DC voltage was applied to the system. Observations showed that the liquid metal in the first channel 4 began to move directionally towards the anode under the influence of the electric field. The corresponding infrared thermogram showed that the temperature of the working area rose rapidly within 2.8 seconds, indicating that the highly thermally conductive liquid metal had completely filled the target working chamber. The reverse experiment showed that when the electric field direction was reversed, the liquid metal in the same area completely withdrew from the working area within 2.4-2.6 seconds, and the temperature of the corresponding area quickly dropped back to the substrate level. The experiment in the second channel 5 also verified the effectiveness of the electric drive. Although the complete filling time was slightly longer due to the influence of fluid exchange efficiency, the expected spatial positioning control was still achieved.

[0083] This experiment visually demonstrates through temperature field changes that a high thermal conductivity medium (liquid metal) can be precisely driven to or removed from a designated working position within a second-scale timescale, providing key technical support for realizing multi-modal control of thermal switches and directly verifying the feasibility of the dynamic thermal management scheme described in this invention.

[0084] In some embodiments, a multimodal capability verification experiment of the multimodal second-level thermal switch of the present invention is provided. Figure 6 This is a schematic diagram illustrating the forward output temperature of a multimodal, second-level thermal switch according to some embodiments of this specification. Figure 7The diagram illustrates the reverse output temperature of a multimodal, second-level thermal switch according to some embodiments of this specification. When the thermal diode is positively thermally biased at 54°C (with the heating temperature and ambient temperature maintained at 70°C and 26±0.6°C respectively), the output temperature of the operating area gradually increases to 43.2°C in the initial state. When an electric field is applied to drive the liquid metal in the upper channel into the operating area (i.e., half-open state 1), the output temperature increases to 45.6°C after 15 minutes. When an electric field is applied to drive the liquid metal in the first channel 4 out of the operating area and the liquid metal in the second channel 5 into the operating area (i.e., half-open state 2), the output temperature significantly increases to 51.3°C after 15 minutes; the output temperature reaches its highest point of 54.1°C when both the first channel 4 and the second channel 5 are filled with liquid metal.

[0085] When the thermal diode is subjected to the same negative thermal bias When T is -54℃, the output temperature of the empty working area gradually increases to 42.9℃ within 15 minutes. When the liquid metal is driven into the working area, the output temperature reaches 43.9℃, 44.3℃, and 44.6℃ respectively in the half-off state 1, half-off state 2, and the initial state when all the liquid metal is in the working area within 15 minutes, verifying that the thermal switch can perform multi-mode temperature control.

[0086] Through the above-mentioned dynamic and programmable thermal management, this system can effectively suppress the thermal deformation of the grating sensor 9 caused by ambient temperature fluctuations or the machine tool's own heating, and significantly improve the long-term operating accuracy and reliability of the CNC machine tool 8 under complex working conditions.

[0087] This application also provides an electronic device, including a potential heat source 7 and a grating sensor 9, wherein a multimodal second-level thermal switch is disposed between the potential heat source 7 and the grating sensor 9 for dynamic thermal protection of the grating sensor 9.

[0088] This invention achieves second-level switching and multi-modal control of thermal switch states by driving the spatial distribution of a high thermal conductivity medium within a double-layer independent flow channel through a non-contact electric field. This breaks through the binary limitation of traditional thermal switches, significantly improves the precision of thermal control, and provides effective dynamic thermal protection for the grating sensor 9. The labyrinth design of the flow channel system also realizes the flow of the high thermal conductivity medium within the flow channel system and in-situ start-stop control, effectively preventing potential corrosion from direct contact between the high thermal conductivity medium and the electrodes, and improving the operational reliability of the thermal switch.

[0089] The multimodal, second-level thermal switch proposed in this invention addresses the limitations of traditional thermal control methods in handling second-level transient heat flow and dual-mode regulation. Through non-contact electric field driving and multimodal flow channel design, it achieves rapid and precise control of heat flow, providing effective dynamic thermal protection for precision measurement components such as grating sensors. This technology is particularly suitable for high-end equipment with instantaneous start-stop and drastic load changes, such as high-precision CNC machine tools and lithography machines. It can effectively suppress thermally induced errors and improve long-term operating accuracy, demonstrating clear application value and promising prospects for widespread adoption.

[0090] The switch comprises a substrate preferably made of PLA material, a dual-layer independent flow channel system, a high thermal conductivity medium filled within the flow channels, two pairs of electrodes disposed on the outside of the flow channels, and a control unit 10 electrically connected to the two pairs of electrodes. Its core lies in using an electric field to drive liquid metal, controlling its spatial distribution within the dual-layer flow channels to achieve second-level switching of thermal resistance states. This constitutes a multi-dimensional control mode with four basic states—fully open, half open, half closed, and fully closed—and their combinations, breaking the binary limitations of traditional thermal switches and solving the fundamental problems of slow response and low degree of freedom in traditional solutions. Its unique flow channel labyrinth 3 and branch structure design further ensure the reliability and accuracy of the control process. Experiments show that this device can suppress the output fluctuation of the grating sensor 9 within ±11.1% under an ambient temperature change of ±10℃, providing a highly efficient dynamic thermal management solution for the grating sensor 9.

[0091] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0092] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A multimodal, second-level thermal switch, characterized in that, include: The flow channel system includes a first flow channel (4) and a second flow channel (5) that are independent of each other. The first flow channel (4) is located on top of the second flow channel (5). The interiors of the first flow channel (4) and the second flow channel (5) are filled with a heat-conducting medium. The electric field driving system includes electrodes (2) disposed on both sides of the first flow channel (4) and the second flow channel (5). A flow channel labyrinth (3) is disposed inside the first flow channel (4) and the second flow channel (5). The end of the flow channel labyrinth (3) near the electrode (2) is connected to the electrode (2).

2. The multimodal second-level thermal switch according to claim 1, characterized in that, The first flow channel (4) and the second flow channel (5) are connected to a branch structure on one side, wherein the electrode (2) on one side is located outside the branch structure, and the flow channel labyrinth (3) connected to the electrode (2) on one side is located inside the branch structure.

3. The multimodal second-level thermal switch according to claim 2, characterized in that, The branching structure is a physical tree-like structure.

4. The multimodal second-level thermal switch according to claim 2, characterized in that, Gas overflow holes are provided on the sides of the first flow channel (4), the second flow channel (5), and the outside of the branch structure, and a hydrophobic and breathable membrane (6) is attached to the gas overflow holes.

5. A multimodal, second-level thermal switch according to claim 1, characterized in that, The flow channel maze (3) includes an access section (31), one end of which is connected to the electrode (2), and the other end of which is connected to a V-shaped section (32). The V-shaped section (32) is connected to an outlet section (33), which is connected to the first flow channel (4) or the second flow channel (5).

6. A multimodal, second-level thermal switching dynamic thermal management system, characterized in that, A multimodal, second-level thermal switch according to any one of claims 1-5 includes: The grating sensor (9) is in contact with the top of the first flow channel (4); The temperature sensing network includes a heat source temperature sensor (11) and a scale body temperature sensor (12), the scale body temperature sensor (12) being located on the scale body of the grating sensor (9); Heat source (7), the heat source temperature sensor (11) is located at the heat source (7); The control system (10) is connected to the heat source temperature sensor (11) and the body temperature sensor (12) by signal connection, and is electrically connected to the electrode (2).

7. A multimodal, second-level thermal switch dynamic thermal management method, characterized in that, The multimodal, second-level thermal switching dynamic thermal management system according to claim 6 includes the following steps: The temperature sensing network monitors the temperature status in real time and transmits the temperature signal to the control system (10). The control system (10) receives the temperature signal, generates a control command based on the temperature signal, and sends the control command to the electric field drive system. The electric field drive system receives the control command and drives the flow channel system to transfer heat to the grating sensor (9) based on the control command, thereby realizing dynamic thermal management.

8. The multimodal, second-level thermal switch dynamic thermal management method according to claim 7, characterized in that, The temperature sensing network monitors the temperature status in real time and transmits the temperature signal to the control system (10), specifically including: The heat source temperature sensor (11) and the scale body temperature sensor (12) respectively detect the temperature signal of the heat source (7) and the temperature signal of the grating sensor (9), and transmit the temperature signal of the heat source (7) and the temperature signal of the grating sensor (9) to the control system (10).

9. A multimodal, second-level thermal switch dynamic thermal management method according to claim 8, characterized in that, The control system (10) receives the temperature signal, generates a control command based on the temperature signal, and sends the control command to the electric field drive system, specifically including: The control system (10) receives the temperature signal of the heat source (7) and the temperature signal of the grating sensor (9), generates a control command based on the temperature signal of the heat source (7) and the temperature signal of the grating sensor (9), and sends the control command to the electrode (2).

10. A multimodal, second-level thermal switch dynamic thermal management method according to claim 9, characterized in that, The electric field driving system receives the control command and, based on the control command, drives the flow channel system to transfer heat to the grating sensor (9), thereby realizing dynamic thermal management, specifically including: The electrode (2) receives the control command and drives the thermally conductive medium to change its spatial position within the first flow channel (4) and the second flow channel (5) based on the control command, thereby realizing dynamic thermal management of the multimodal second-level thermal switch, wherein the dynamic thermal management includes: In the thermally conductive state, when the equipment is in a low-temperature operating condition or in the start-up state, the thermally conductive medium fills the first flow channel (4) and the second flow channel (5), allowing the heat of the first flow channel (4) and the second flow channel (5) to be transferred to the grating sensor (9). In the medium thermal conductivity state, when under medium load or temperature fluctuation conditions, the thermally conductive medium fills the first flow channel (4) and leaves the second flow channel (5), allowing the heat of the first flow channel (4) to be transferred to the grating sensor (9), or the thermally conductive medium leaves the first flow channel (4) and fills the second flow channel (5), allowing the heat of the second flow channel (5) to be transferred to the grating sensor (9). In the heat-resistant state, when under high temperature or heavy load conditions, the heat-conducting medium leaves the first flow channel (4) and the second flow channel (5), preventing the heat from the first flow channel (4) and the second flow channel (5) from being transferred to the grating sensor (9).

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