Slide-wire rheostat type thermal switch
Through the design of sliding line varistor-type thermal switch, the problem of insufficient thermal conductivity and switching speed in low-temperature environments is solved, and the high thermal conductivity and continuous controllable temperature control effect is achieved, the structure is simplified, and the experimental accuracy and response speed are improved.
Patent Information
- Application Number
- CN202510684511.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-26
- Publication Date
- 2025-08-29
AI Technical Summary
The existing thermal switches have insufficient switching speed and thermal conductivity ratio in low-temperature environments, their structure is complex and they are prone to mechanical vibration or magnetic interference, which affects the experimental accuracy.
The sliding line varistor type thermal switch is adopted, and the elastic abutment structure of thermal conductivity spirals and metal slides is used, combined with thermal conductivity copper braids and beryllium copper shrapnel, the thermal conductivity coefficient is achieved through the thermal conductivity copper slider and the driving structure, and the friction loss is reduced by using sapphire hemisphere contacts, and the structure is simplified to reduce mechanical vibration and magnetic interference.
It realizes a high thermal conductivity ratio and continuously controllable temperature control effect, improves experimental accuracy, reduces mechanical vibration and magnetic interference, and improves the response speed and sensitivity of the thermal switch.
Smart Images
Figure CN120565341A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of thermal switches, and in particular to a sliding-wire rheostat type thermal switch. Background Art
[0002] Thermal switches are widely used in temperature control of low-temperature systems, heat exchange of adiabatic demagnetization refrigerators, etc.
[0003] Commonly used thermal switches include air-gap thermal switches, mechanical or magnetically driven thermal switches, and thermal switches implemented using superconducting materials or phase-change materials. The main problems they face in low-temperature environments include: insufficient switching speed and thermal conductivity, resulting in incomplete transitions between the switching states; complex structures and the susceptibility to mechanical vibration or magnetic interference, which affects experimental accuracy. Summary of the Invention
[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a sliding-wire rheostat thermal switch, comprising an insulating housing, a highly insulating support rod disposed within the insulating housing, a rheostat disposed on the highly insulating support rod, the rheostat comprising a thermally conductive spiral and a metal slider, the metal slider elastically abutting the thermally conductive spiral, a thermally conductive copper braid connected between the metal slider and the highly insulating support rod, and a hemispherical contact disposed at one end of the metal slider abutting the thermally conductive spiral.
[0005] Preferably, the two ends of the high thermal insulation support rod are respectively a cold end plane and a hot end plane.
[0006] Preferably, the heat-conducting copper braid is connected to the cold end plane.
[0007] Preferably, the variable resistor further includes a displacement structure, which includes a heat-conducting copper slider slidably arranged in the insulating shell, and one end of the heat-conducting copper slider is connected to a driving structure.
[0008] Preferably, the heat-conducting copper slider and the metal slide are elastically rotatably connected, and the heat-conducting copper slider and the heat-conducting copper braid are connected.
[0009] Preferably, the metal slide is a beryllium copper spring, a rotating shaft is fixed to the beryllium copper spring, and the rotating shaft is rotatably connected to the heat-conducting copper slider.
[0010] Preferably, the hemispherical contact is fixed to the beryllium copper shrapnel, and the hemispherical contact is made of sapphire.
[0011] Preferably, one end of the beryllium copper shrapnel rotatably connected to the thermally conductive copper slider abuts against a spring, and the other end of the spring abuts against the thermally conductive copper slider.
[0012] Preferably, both ends of the spring are fixed with heat insulation gaskets.
[0013] Preferably, the driving structure includes a connecting rod and a driving member, the connecting rod is rotatably connected to the thermally conductive copper slider, the connecting rod and the insulating shell are threadedly connected, and the driving member is fixed to one end of the connecting rod extending out of the insulating shell.
[0014] The beneficial effects of the present invention are: the thermal switch is realized by utilizing the structure of sliding variable resistance, which can achieve a high thermal conductivity ratio, continuous and high-precision control of the thermal conductivity coefficient, and can be used to achieve continuous temperature control over a large range. On the other hand, the purpose of continuous control of the thermal conductivity coefficient can be achieved. The metal slider adopts beryllium copper spring, which has good elasticity and thermal conductivity at low temperature. The use of wear-resistant and thermally conductive sapphire at the contact end reduces the friction loss of the spring. The elastic rotating connection at the other end of the metal slider can compensate for the poor contact caused by wear at the front end of the spring. At the same time, the simple structural design reduces mechanical vibration or magnetic interference, thereby improving the experimental accuracy.
[0015] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions of the implementation methods of the present application, the following is a brief introduction to the drawings required for use in the implementation methods. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.
[0017] Figure 1 1 is a schematic structural diagram of a sliding-wire rheostat type thermal switch according to an embodiment of the present application;
[0018] Figure 2 Schematic diagram of the structure between the thermally conductive copper slider and the beryllium copper shrapnel according to an embodiment of the present application.
[0019] Icons: 1. High insulation support rod; 2. Cold end plane; 3. Hot end plane; 4. Thermal conductive spiral; 5. Thermal conductive copper slider; 6. Beryllium copper shrapnel; 61. Rotating shaft; 62. Hemispherical contact; 63. Spring; 631. Thermal insulation gasket; 7. Thermal conductive copper braid; 8. Connecting rod; 9. Driving part. DETAILED DESCRIPTION
[0020] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.
[0021] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0022] like Figure 1 and 2 As shown, a sliding-wire rheostat type thermal switch according to an embodiment of the present application includes an insulating shell, in which a high-insulation support rod 1 is arranged. Specifically, the two ends of the high-insulation support rod 1 are a cold end plane 2 and a hot end plane 3 respectively, and a rheostat is arranged on the high-insulation support rod 1. The rheostat includes a thermally conductive spiral 4 and a metal slider, and the metal slider and the thermally conductive spiral 4 are elastically abutted against each other. A thermally conductive copper braid 7 is connected between the metal slider and the high-insulation support rod 1, and the thermally conductive copper braid 7 is woven from multiple strands of fine copper wire and has good thermal conductivity and flexibility. The thermally conductive copper braid 7 is connected to the hot end plane 3, and a hemispherical contact 62 is provided at one end of the metal slider abutting against the thermally conductive spiral 4.
[0023] It should be noted that the cold end plane 2 usually has less contact with the external environment and the temperature is relatively low, while the hot end plane 3 is more susceptible to the influence of external heat sources and the temperature is higher. The high thermal insulation performance of the high-insulation support rod 1 can effectively prevent the transfer of heat on itself, ensuring that the temperature difference between the cold end plane 2 and the hot end plane 3 can be maintained, thereby improving the sensitivity and accuracy of the thermal switch.
[0024] It should be further noted that the spiral shape of the thermally conductive spiral 4 increases its length, thereby widening the adjustable resistance range. Furthermore, the spiral structure facilitates heat transfer and distribution. When current passes through the thermally conductive spiral 4, a certain amount of heat is generated due to the resistive properties of the metal material. Furthermore, the thermally conductive spiral 4 is also affected by external temperature fluctuations, and its resistance value changes with increasing or decreasing temperature.
[0025] Among them, the variable resistor also includes a displacement structure, which includes a thermally conductive copper slider 5 slidingly arranged in an insulating shell, one end of the thermally conductive copper slider 5 is connected to a driving structure, wherein the thermally conductive copper slider 5 and the metal slider are elastically rotatably connected, and the thermally conductive copper slider 5 and the thermally conductive copper braid 7 are connected.
[0026] It can be understood that one end of the thermal copper braid 7 is connected to the cold end plane 2, and the other end is connected to the thermal copper slider 5. Its function is to transfer the heat on the hot end plane 3 to the cold end plane 2 through the beryllium copper shrapnel 6, the thermal copper slider 5 and the thermal copper braid 7, maintaining a suitable temperature relationship between the cold end plane 2 and the hot end plane 3, so that the thermal switch can work accurately according to the design requirements.
[0027] Among them, the driving structure includes a connecting rod 8 and a driving member 9. The connecting rod 8 is rotatably connected to the heat-conducting copper slider 5. The connecting rod 8 and the insulating shell are threadedly connected. The driving member 9 is fixed to one end of the connecting rod 8 extending out of the insulating shell.
[0028] In a specific embodiment of the present application, the metal slider is a beryllium copper shrapnel 6, which has good elasticity and thermal conductivity at low temperatures, which enables it to be in close contact with the thermally conductive spiral 4 to ensure the conductivity of the circuit. A rotating shaft 61 is fixed to the beryllium copper shrapnel 6, and the rotating shaft 61 is rotatably connected to the thermally conductive copper slider 5. It should be noted that the rotating shaft 61 is preferably made of a metal material with good thermal conductivity, such as copper or silver. This ensures that heat can be quickly transferred from the beryllium copper shrapnel 6 to the rotating shaft 61, and then transferred to other components through the rotating shaft 61, thereby improving the response speed of the thermal switch.
[0029] It should be noted that hemispherical contact 62 is fixed to beryllium copper spring 6 and is made of sapphire. Sapphire has extremely high hardness and wear resistance, which can maintain good contact during long-term use and reduce heat conduction losses. In addition, sapphire has excellent thermal conductivity, which can quickly transfer heat to beryllium copper spring 6, thereby improving the sensitivity of the thermal switch.
[0030] In a specific embodiment of the present application, one end of the beryllium copper shrapnel 6 facing the heat-conducting copper slider 5 is in contact with a spring 63, and the other end of the spring 63 is in contact with the heat-conducting copper slider 5. It can be understood that when the beryllium copper shrapnel 6 contacts the heat-conducting spiral 4, the spring 63 is compressed, generating a certain elastic force. This elastic force can maintain close contact between the beryllium copper shrapnel 6 and the heat-conducting spiral 4, avoiding poor contact. At the same time, the elasticity of the spring 63 can also play a certain buffering role. When the thermal switch is subjected to external vibration or impact, the spring 63 can absorb some of the energy and protect the internal components from damage.
[0031] It should be noted that both ends of the spring 63 are fixed with thermal insulation gaskets 631, which can effectively prevent heat from being transferred from the beryllium copper spring 6 or the heat-conducting copper slider 5 to the spring 63, thereby reducing the temperature of the spring 63 and extending the service life of the spring 63.
[0032] From this, it can be understood that by rotating the driving member 9, the connecting rod 8 can be axially displaced on the insulating shell, thereby driving the thermal copper slider 5 and the beryllium copper shrapnel 6 thereon to axially displace relative to the thermal spiral 4. Through the displacement of the beryllium copper shrapnel 6 on the thermal spiral 4, the length of the thermal spiral 4 connected to the circuit is changed, thereby continuously adjusting the resistance in the circuit. When the temperature change causes the resistance of the thermal spiral 4 to change, combined with the adjustment of the position of the beryllium copper shrapnel 6 on the thermal spiral 4, the current in the circuit can be changed. When the current reaches or exceeds a certain threshold, the switching element connected to the circuit can be triggered to operate, thereby realizing the function of the thermal switch. Specifically, when the external temperature rises, the resistance value of the thermal spiral 4 will increase. At this time, if the length of the thermal spiral 4 connected to the circuit is reduced by adjusting the position of the beryllium copper shrapnel 6 on the thermal spiral 4, the resistance value in the circuit will decrease and the current will increase. On the contrary, when the external temperature decreases, the resistance value of the thermal spiral 4 will decrease. At this time, if the position of the beryllium copper spring 6 on the thermal spiral 4 is adjusted to increase the length of the thermal spiral 4 connected to the circuit, the resistance value in the circuit will increase and the current will decrease.
[0033] In another embodiment of the present application, the driving structure can also be implemented by differential spiral coupling (electric or manual), piezoelectric drive or pneumatic drive.
[0034] It should be noted that the specific models and specifications of the thermal spiral 4, spring 63 and thermal insulation gasket 631 need to be selected and determined according to the actual specifications of the device. The specific selection calculation method adopts the existing technology in this field, so it will not be described in detail.
[0035] The above are only specific embodiments of the present application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.
Claims
1. A sliding-wire rheostat type thermal switch, characterized in that: include: An insulating shell is provided inside the insulating shell, a high-insulation support rod (1) is provided on the high-insulation support rod (1), the variable resistor comprises a heat-conducting spiral (4) and a metal slide, the metal slide and the heat-conducting spiral (4) are elastically abutted, a heat-conducting copper braid (7) is connected between the metal slide and the high-insulation support rod (1), and a hemispherical contact (62) is provided at one end of the metal slide abutting against the heat-conducting spiral (4).
2. A sliding-wire rheostat type thermal switch according to claim 1, characterized in that: The two ends of the high thermal insulation support rod (1) are respectively a cold end plane (2) and a hot end plane (3).
3. A sliding-wire rheostat type thermal switch according to claim 2, characterized in that: The heat-conducting copper braid (7) is connected to the cold end plane (2).
4. A sliding-wire rheostat type thermal switch according to claim 1, characterized in that: The variable resistor further comprises a displacement structure, wherein the displacement structure comprises a heat-conducting copper slider (5) slidably arranged in the insulating shell, and one end of the heat-conducting copper slider (5) is connected to a driving structure.
5. A sliding-wire rheostat type thermal switch according to claim 4, characterized in that: The heat-conducting copper slider (5) and the metal slide are elastically rotatably connected, and the heat-conducting copper slider (5) and the heat-conducting copper braid (7) are connected.
6. A sliding-wire rheostat type thermal switch according to claim 5, characterized in that: The metal slide is a beryllium copper spring (6), a rotating shaft (61) is fixedly connected to the beryllium copper spring (6), and the rotating shaft (61) is rotatably connected to the heat-conducting copper slider (5).
7. A sliding-wire rheostat type thermal switch according to claim 6, characterized in that: The hemispherical contact (62) is fixed to the beryllium copper spring (6), and the hemispherical contact (62) is made of sapphire.
8. The sliding-wire rheostat type thermal switch according to claim 6, characterized in that: One end of the beryllium copper shrapnel (6) rotatably connected to the heat-conducting copper slider (5) abuts against a spring (63), and the other end of the spring (63) abuts against the heat-conducting copper slider (5).
9. A sliding-wire rheostat type thermal switch according to claim 8, characterized in that: Both ends of the spring (63) are respectively fixed with heat insulation gaskets (631).
10. The sliding-wire rheostat type thermal switch according to claim 4, characterized in that: The driving structure comprises a connecting rod (8) and a driving member (9), wherein the connecting rod (8) is rotatably connected to the heat-conducting copper slider (5), the connecting rod (8) and the insulating shell are threadedly connected, and the driving member (9) is fixed to one end of the connecting rod (8) extending out of the insulating shell.