A parallel robot temperature control device for vacuum low-temperature environment

Abstract

The present application relates to aerospace or vacuum cryogenic technology field, especially to a kind of parallel robot temperature control device for under vacuum cryogenic environment, including upper platform heat preservation cover, lower platform heat preservation cover, multilayer heat insulation component, temperature sensor, heating sheet and heat insulation pad;Upper platform heat preservation cover is installed on upper platform, and lower platform heat preservation cover is installed on lower platform;By the setting of parallel robot temperature control device, several heating zones are formed in parallel robot, and temperature sensor is arranged in each heating zone;Telescopic rod is connected with upper platform through the joint of upper hinge, and telescopic rod and motor are fixed on motor support, and motor support is connected with lower platform through the joint of lower hinge;Provided temperature control device can effectively solve the technical problems of large stroke, large angle fast motion of parallel robot under vacuum cryogenic environment, many movable joints, unfixing position of bare position, unable to be covered by multilayer heat insulation component, and further cause serious heat leakage, and high temperature control difficulty.

Description

Technical Field

[0001] This invention belongs to the field of aerospace or vacuum cryogenic technology, and particularly relates to a temperature control device for parallel robots in vacuum cryogenic environments. Background Technology

[0002] With the increasing complexity of space exploration missions, such as space station construction, satellite repair, deep space exploration, and on-orbit assembly, the demand for high-precision space robots is extremely urgent. The upper and lower platforms and the telescopic rod are connected by joint hinges. The extension and retraction of the telescopic rod causes it to swing around the hinge, and the amplitude of this swing is determined by the structure of the parallel robot. Therefore, it is impossible to completely cover the hinge parts and the moving parts of the telescopic rod, leaving these components exposed to the cold, dark environment of space or the low temperatures of the vacuum on Earth, resulting in significant heat leakage and extremely difficult temperature control. Under these circumstances, to ensure the normal operation of the parallel robot and the temperature control of each critical component, reasonable and efficient temperature control measures are needed.

[0003] Commonly used thermal control measures include: first, covering the surface with multiple layers of heat insulation components, making a thermal control coating, and achieving temperature control by adjusting the heat exchange between the inside and outside; second, attaching heating elements for temperature compensation, and ensuring the overall internal energy level by controlling the temperature control power and heating time. Summary of the Invention

[0004] In view of this, in order to solve the technical problem of existing parallel robots moving rapidly with large strokes and large angles in vacuum low temperature environments, having many moving joints and unfixed exposed positions, making it impossible to completely cover them with multi-layer heat insulation components, resulting in serious heat leakage and high temperature control difficulty, this invention provides a novel temperature control device for parallel robots in vacuum low temperature environments.

[0005] To achieve the above objectives, the technical solution created by this invention is implemented as follows: This invention provides a temperature control device for a parallel robot in a vacuum cryogenic environment. The structure of the parallel robot includes an upper platform, an upper hinge, a telescopic rod, a motor, a motor support, a lower hinge, and a lower platform. The telescopic rod is connected to the upper platform via the joint of the upper hinge. Both the telescopic rod and the motor are fixed on the motor support. The motor support is connected to the lower platform via the joint of the lower hinge. The motor includes a side close to the external space, a side away from the external space, and two sides. The parallel robot temperature control device includes an upper platform insulation cover, a lower platform insulation cover, a multi-layer heat insulation component, a temperature sensor, a heating element, and a heat insulation pad; the upper platform insulation cover is installed on the upper platform, and the lower platform insulation cover is installed on the lower platform; through the setting of the parallel robot temperature control device, several heating zones are formed in the parallel robot, and the temperature sensor is set in each heating zone.

[0006] Furthermore, the outer surface of the upper platform insulation cover, the outer surface of the lower platform insulation cover, the outer surface of the upper platform, the outer surface of the lower platform, the non-connected area of ​​the inner surface of the upper platform, the non-connected area of ​​the inner surface of the lower platform, the telescopic rod, the two sides of the motor, and the motor support are all covered with the multi-layer heat insulation component.

[0007] Furthermore, the upper platform insulation cover is installed with heat insulation pads between itself and the upper platform, between the lower platform insulation cover and the lower platform, and between the motor and the motor support; the heat insulation pads are made of titanium alloy, fiberglass, or polyimide.

[0008] Furthermore, the inner surface of the upper platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the upper platform insulation cover is not less than 0.8; and / or, the inner surface of the lower platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the lower platform insulation cover is not less than 0.8.

[0009] Furthermore, the upper platform insulation cover is mechanically connected to the upper platform through three upper fixing points, which are distributed at 120° equiangular intervals; the lower platform insulation cover is mechanically connected to the lower platform through three lower fixing points, which are distributed at 120° equiangular intervals; the heat insulation pad is provided at each upper fixing point and at each lower fixing point.

[0010] Furthermore, the length of the upper platform insulation cover extends downwards, and the length of the upper platform insulation cover covers the upper hinge; the length of the lower platform insulation cover extends upwards, and the length of the lower platform insulation cover covers the lower hinge.

[0011] Furthermore, heating elements are attached to the outer surfaces of the upper platform insulation cover, the lower platform insulation cover, the side of the motor near the external space, the side of the motor away from the external space, the side of the telescopic rod near the external space, and the side of the telescopic rod away from the external space.

[0012] Furthermore, the heating element is made of a flexible thin-film heating element; the heating elements are arranged in a spiral or grid pattern.

[0013] Furthermore, a ring of heating elements is attached to the outer surface of the upper platform insulation cover along the circumferential direction, and a ring of heating elements is attached to the inner surface of the upper platform insulation cover along the circumferential direction; a ring of heating elements is attached to the outer surface of the lower platform insulation cover along the circumferential direction, and a ring of heating elements is attached to the inner surface of the lower platform insulation cover along the circumferential direction.

[0014] Furthermore, the temperature sensor is a thermistor, thermocouple, or platinum resistance thermometer.

[0015] Compared with the prior art, the present invention can achieve the following beneficial effects: The present invention provides a temperature control device for parallel robots in a vacuum cryogenic environment. When the parallel robot is working, it can actively control the temperature by raising the temperature of the insulation cover and radiating heat inward, thereby increasing the overall temperature level of the internal space. Furthermore, the active thermal control of the motor and telescopic rod ensures the temperature index of the joint hinges and exposed parts of the telescopic rod. The length of the insulation cover can be flexibly adjusted according to the activity space of the parallel robot on the platform. The insulation cover is easy to install and maintain, has a flat surface that facilitates the attachment of heating elements, and can be flexibly applied to other similar aerospace devices as needed.

[0016] The present invention provides a temperature control device for parallel robots in a vacuum cryogenic environment. A heat dissipation surface is provided on the motor surface to prevent excessive temperature during motor operation. Simultaneously, thermal insulation is used between the motor and its support to isolate the motor's influence on the telescopic rod. A high-emissivity coating, such as black paint or black anodized coating, is applied to the inside of the insulation cover to increase infrared emissivity and improve the efficiency of energy radiation from the insulation cover into the interior. Multiple layers of thermal insulation components are applied to the outer surface of the insulation cover, the telescopic rod, and the motor to reduce the impact of external heat flow on the parallel robot's temperature and prevent excessive heat loss from critical robot components into the cryogenic space. Furthermore, thermal insulation materials are used appropriately to ensure good thermal insulation between the motor and its support, and between the upper and lower platforms and the insulation cover. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the structure of a parallel robot temperature control device for use in a vacuum cryogenic environment, as described in the embodiments of the present invention. Figure 2 This is a schematic diagram of the thermal control measures of a parallel robot temperature control device for use in a vacuum cryogenic environment, as described in an embodiment of the present invention.

[0018] Figure label: 1. Upper platform; 2. Upper platform insulation cover; 3. Telescopic rod; 4. Motor; 5. Motor support; 6. Lower hinge; 7. Lower platform; 8. Lower platform insulation cover; 9. Upper hinge; 10. Multi-layer heat insulation component; 11. Temperature sensor; 12. Heating element; 13. Heat insulation pad. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., 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, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] In a specific embodiment of the present invention, a temperature control device for a parallel robot in a vacuum cryogenic environment is provided. The parallel robot structure includes an upper platform, an upper hinge, a telescopic rod, a motor, a motor support, a lower hinge, and a lower platform. The telescopic rod is connected to the upper platform via the joint of the upper hinge. Both the telescopic rod and the motor are fixed on the motor support. The motor support is connected to the lower platform via the joint of the lower hinge. The motor includes a side close to the external space, a side away from the external space, and two sides. The motor is mainly used to drive the telescopic rod to move. The parallel robot temperature control device includes an upper platform insulation cover, a lower platform insulation cover, multi-layer heat insulation components, temperature sensors, heating elements, and heat insulation pads. The upper platform insulation cover is installed on the upper platform, and the lower platform insulation cover is installed on the lower platform. Through the configuration of the parallel robot temperature control device, several heating zones are formed in the parallel robot. The temperature sensors are installed in each heating zone. Specifically, the parallel robot temperature control device sets 17 heating zones in the parallel robot, distributed on the bottom surface of the upper platform, the upper platform insulation cover, the body of each telescopic rod, each motor, the top surface of the lower platform, and the lower platform insulation cover. Temperature sensors are installed in the vicinity of the heating elements in each heating zone. The temperature sensors can be thermistors, thermocouples, or platinum resistance thermometers, capable of acquiring temperature signals in real time and transmitting them to the controller. The controller compares the measured values ​​with the set values ​​using a PID algorithm, generates adjustment commands, and dynamically adjusts the output duty cycle of the heating elements to achieve closed-loop temperature control, ensuring that the temperature of each heating zone remains stable within the target range.

[0024] In a specific embodiment, the outer surfaces of the upper platform insulation cover, the lower platform insulation cover, the upper platform, the lower platform, the non-connected areas of the inner surfaces of the upper and lower platforms, the telescopic rod, the two sides of the motor, and the motor support are all covered with the multi-layer heat insulation assembly. The upper platform insulation cover is installed with heat insulation pads between itself and the upper platform, between itself and the lower platform insulation cover, and between the motor and the motor support. Except for the joints between the upper and lower platforms and the lower hinge, the movable parts of the telescopic rod, the inner surfaces of the upper and lower platform insulation covers, and the side of the motor closest to the internal space, the other parts are covered with the multi-layer heat insulation assembly. The multi-layer heat insulation assembly is a commonly used vacuum multi-layer heat insulation assembly made of several reflective screens and interleaved reflectors, and its main materials are double-sided aluminized film and polyester mesh. In this invention, the heat insulation pad is made of titanium alloy, fiberglass, or polyimide. The inner surface of the upper platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the upper platform insulation cover is not less than 0.8; and / or, the inner surface of the lower platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the lower platform insulation cover is not less than 0.8.

[0025] In a specific implementation, the upper platform insulation cover has both heating elements and multi-layer heat insulation components on its outer surface, and the lower platform insulation cover also has both heating elements and multi-layer heat insulation components on its outer surface. The heating elements can be flexible polyimide film heaters, which can be embedded between the inner layer of the multi-layer heat insulation components and the outer surfaces of the upper and lower platform insulation covers. The surface of the heating elements is coated with thermally conductive silicone grease and directly adheres to the shell surface. The fixing methods for the multi-layer heat insulation components may include mechanical fixing, such as sewing, strapping, adhesives, etc. The covering method of the multi-layer heat insulation components can be layered wrapping, edge sealing, overlapping design, etc., to ensure that there are no thermal bridges and gaps.

[0026] In a specific implementation, the upper platform insulation cover is mechanically connected to the upper platform via three upper fixing points, which are distributed at 120° equiangular intervals. The lower platform insulation cover is mechanically connected to the lower platform via three lower fixing points, which are also distributed at 120° equiangular intervals. A heat insulation pad is installed at each upper fixing point and at each lower fixing point. The upper platform insulation cover extends downwards, covering the upper hinge, to avoid affecting the movement of the upper platform and the telescopic rod. The lower platform insulation cover extends upwards, covering the lower hinge, to avoid affecting the movement of the lower platform and the telescopic rod. Heating pads are attached to the outer surfaces of the upper and lower platform insulation covers, the side of the motor closest to the external space, the side of the motor furthest from the external space, the side of the telescopic rod closest to the external space, and the side of the telescopic rod furthest from the external space.

[0027] In a specific implementation, each heating element is custom-made with a fixed resistance value. Specifically, the resistance value is determined by the structure of the parallel robot. The required power is calculated through simulation, and then the resistance value is calculated using R=U² / P. With a constant voltage, the heating time is controlled to regulate the temperature of the heating elements. The internal temperature level of the parallel robot is determined by the power of the heating elements on the heating cover. The power of the heating elements used in this invention is calculated through precise simulation and ensures that the radiated energy can keep the hinge temperature above 0°C even in low-temperature environments. The temperature of the insulation cover is determined by controlling the duty cycle of heating on the insulation cover, i.e., the heating time. Temperature sensors on the upper and lower platform insulation covers provide feedback as a control mechanism. In a specific implementation, the heating element is a flexible thin-film heating element. The heating element is connected to the corresponding surface using a high-efficiency thermally conductive material, such as thermally conductive adhesive or grease, to improve heat conduction efficiency, reduce heat loss, and ensure that heat is quickly and evenly distributed to the heating area. The arrangement of the heating elements can be flexibly adjusted according to specific structures and requirements; for example, a spiral or grid distribution can be used to achieve a more uniform heat distribution and avoid hot spots. Specifically, a ring of heating elements is attached to the outer surface of the upper platform insulation cover along the circumferential direction, and a ring of heating elements is attached to the inner surface of the upper platform insulation cover along the circumferential direction; a ring of heating elements is attached to the outer surface of the lower platform insulation cover along the circumferential direction, and a ring of heating elements is attached to the inner surface of the lower platform insulation cover along the circumferential direction. Preferably, the heating elements on the upper and lower platform insulation covers are attached in multiple pieces to ensure convenient installation.

[0028] In a specific embodiment, the present invention also provides a parallel robot, which includes the parallel robot temperature control device of the present invention and can be used in a vacuum low-temperature environment.

[0029] The present invention provides a temperature control device for parallel robots in a vacuum cryogenic environment. When the parallel robot is working, it can actively control the temperature by raising the temperature of the insulation cover and radiating heat inward, thereby increasing the overall temperature level of the internal space. Furthermore, the active thermal control of the motor and telescopic rod ensures the temperature index of the joint hinges and exposed parts of the telescopic rod. The length of the insulation cover can be flexibly adjusted according to the activity space of the parallel robot on the platform. The insulation cover is easy to install and maintain, has a flat surface that facilitates the attachment of heating elements, and can be flexibly applied to other similar aerospace devices as needed.

[0030] The present invention provides a temperature control device for parallel robots in a vacuum cryogenic environment. A heat dissipation surface is provided on the motor surface to prevent excessive temperature during motor operation. Simultaneously, thermal insulation is used between the motor and its support to isolate the motor's influence on the telescopic rod. A high-emissivity coating, such as black paint or black anodized coating, is applied to the inside of the insulation cover to increase infrared emissivity and improve the efficiency of energy radiation from the insulation cover into the interior. Multiple layers of thermal insulation components are applied to the outer surface of the insulation cover, the telescopic rod, and the motor to reduce the impact of external heat flow on the parallel robot's temperature and prevent excessive heat loss from critical robot components into the cryogenic space. Furthermore, thermal insulation materials are used appropriately to ensure good thermal insulation between the motor and its support, and between the upper and lower platforms and the insulation cover.

[0031] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] like Figure 1 and Figure 2 The figures show a schematic diagram of the structure and thermal control measures of a parallel robot temperature control device in a vacuum cryogenic environment, according to a specific embodiment of the present invention. As can be seen from the figures, the parallel robot structure includes an upper platform 1, an upper hinge 9, a telescopic rod 3, a motor 4, a motor support 5, a lower hinge 6, and a lower platform 7. The telescopic rod 3 is connected to the upper platform 1 via the joint of the upper hinge 9. Both the telescopic rod 3 and the motor 4 are fixed to the motor support 5, which is connected to the lower platform 7 via the joint of the lower hinge 6. The motor 4 includes a side close to the external space, a side away from the external space, and two sides. The parallel robot temperature control device includes an upper platform insulation cover 2, a lower platform insulation cover 8, a multi-layer thermal insulation component 10, a temperature sensor 11, a heating element 12, and a thermal insulation pad 13. The upper platform insulation cover 2 is installed on the upper platform 1, and the lower platform insulation cover 8 is installed on the lower platform 7. Through the configuration of the parallel robot temperature control device, several heating zones are formed in the parallel robot, and the temperature sensor 11 is installed in each heating zone.

[0033] Specifically, the upper platform insulation cover 2 is mechanically connected to the upper platform 1 through three upper fixing points, which are distributed at 120° equiangular angles; the lower platform insulation cover 8 is mechanically connected to the lower platform 7 through three lower fixing points, which are also distributed at 120° equiangular angles; the upper and lower fixing points are located at the outer edge of the contact surface between the platform and the insulation cover, respectively, and are mechanically connected by titanium alloy fastening bolts, with a titanium alloy heat insulation pad embedded at each fixing point.

[0034] Specifically, the outer surfaces of the upper platform insulation cover 2, the lower platform insulation cover 8, the upper platform 1, the lower platform 7, the non-connected areas of the inner surface of the upper platform 1, the non-connected areas of the inner surface of the lower platform 7, the telescopic rod 3, the two sides of the motor 4, and the motor support 5 are all covered with multi-layer heat insulation components 20; the upper platform insulation cover 2 and the upper platform 1, the lower platform insulation cover 8 and the lower platform 7, and the motor 4 and the motor support 5 are all heat-insulated by heat insulation pads 13; the inner surfaces of the upper platform insulation cover 2 and the lower platform insulation cover 8 are uniformly covered with a black paint coating or a black anodized coating with an emissivity of not less than 0.8; a ring of heating elements 12 is pasted around the outer and inner surfaces of the upper platform insulation cover 2 and the lower platform insulation cover 8, and multiple heating elements 12 are pasted around the outer and inner surfaces of the lower platform insulation cover 8 to ensure convenient installation.

[0035] The novel temperature control device for parallel robots in vacuum cryogenic environments provided by this invention can effectively solve the technical problem of severe heat leakage and high temperature control difficulty caused by the large stroke, large angle, rapid movement, many moving joints, and unfixed exposed positions of parallel robots in vacuum cryogenic environments, which cannot be completely covered by multi-layer heat insulation components.

[0036] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0037] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A temperature control device for parallel robots in a vacuum cryogenic environment, characterized in that: The structure of a parallel robot includes an upper platform, an upper hinge, a telescopic rod, a motor, a motor support, a lower hinge, and a lower platform. The telescopic rod is connected to the upper platform via the joint of the upper hinge. Both the telescopic rod and the motor are fixed on the motor support. The motor support is connected to the lower platform via the joint of the lower hinge. The motor includes a side close to the external space, a side away from the external space, and two sides. The parallel robot temperature control device includes an upper platform insulation cover, a lower platform insulation cover, a multi-layer heat insulation component, a temperature sensor, a heating element, and a heat insulation pad; the upper platform insulation cover is installed on the upper platform, and the lower platform insulation cover is installed on the lower platform; through the setting of the parallel robot temperature control device, several heating zones are formed in the parallel robot, and the temperature sensor is set in each heating zone; The outer surface of the upper platform insulation cover, the outer surface of the lower platform insulation cover, the outer surface of the upper platform, the outer surface of the lower platform, the non-connected part of the inner surface of the upper platform, the non-connected part of the inner surface of the lower platform, the telescopic rod, the two sides of the motor, and the motor support are all covered with the multi-layer heat insulation component. Except for the joints between the platform and the hinges, the moving parts of the telescopic rod, the inner surface of the upper platform insulation cover, the inner surface of the lower platform insulation cover, and the side of the motor near the internal space, the other parts are covered with multiple layers of heat insulation components. The upper platform insulation cover is mechanically connected to the upper platform through three upper fixing points, which are distributed at 120° equal angles; the lower platform insulation cover is mechanically connected to the lower platform through three lower fixing points, which are distributed at 120° equal angles. The upper and lower fixing points are located on the outer edge of the contact surface between the platform and the insulation cover, respectively, and are mechanically connected by titanium alloy fastening bolts. A titanium alloy heat insulation pad is embedded at each fixing point. The upper platform insulation cover extends downwards and its length covers the upper hinge; the lower platform insulation cover extends upwards and its length covers the lower hinge. The heating element is attached to the outer surface of the upper platform insulation cover, the outer surface of the lower platform insulation cover, the side of the motor near the external space, the side of the motor away from the external space, the side of the telescopic rod near the external space, and the side of the telescopic rod away from the external space. The heating element is made of a flexible thin-film heating element; the heating elements are arranged in a spiral or grid pattern.

2. The temperature control device for parallel robots in a vacuum cryogenic environment according to claim 1, characterized in that: The motor and the motor support are installed with thermal insulation through the thermal insulation pad; the thermal insulation pad is made of titanium alloy, fiberglass or polyimide.

3. The temperature control device for parallel robots in a vacuum cryogenic environment according to claim 1, characterized in that: The inner surface of the upper platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the upper platform insulation cover is not less than 0.8; and / or, the inner surface of the lower platform insulation cover is uniformly covered with a black paint coating or a black anodized coating, and the emissivity of the inner surface of the lower platform insulation cover is not less than 0.

8.

4. The temperature control device for parallel robots in a vacuum cryogenic environment according to claim 1, characterized in that: The outer surface of the upper platform insulation cover is circumferentially covered with a ring of heating elements, and the inner surface of the upper platform insulation cover is circumferentially covered with a ring of heating elements; the outer surface of the lower platform insulation cover is circumferentially covered with a ring of heating elements, and the inner surface of the lower platform insulation cover is circumferentially covered with a ring of heating elements.

5. The temperature control device for parallel robots in a vacuum cryogenic environment according to claim 1, characterized in that: The temperature sensor is a thermistor, thermocouple, or platinum resistance thermometer.

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